mdbx: вливание ветки devel в master.

56 files changed, 8997 insertions(+), 4507 deletions(-)

CMakeLists.txt

@@ -305,7 +305,7 @@ else()
         "${CMAKE_CURRENT_SOURCE_DIR}/test/valgrind_suppress.txt"
         CACHE FILEPATH "Suppressions file for Valgrind" FORCE)
       set(MEMORYCHECK_COMMAND_OPTIONS
-        "--trace-children=yes --leak-check=full --track-origins=yes --error-exitcode=42 --error-markers=@ --errors-for-leak-kinds=definite --fair-sched=yes --suppressions=${MEMORYCHECK_SUPPRESSIONS_FILE}"
+        "--trace-children=yes --leak-check=full --track-origins=yes --track-origins=yes --error-exitcode=42 --error-markers=@ --errors-for-leak-kinds=definite --fair-sched=yes --suppressions=${MEMORYCHECK_SUPPRESSIONS_FILE}"
         CACHE STRING "Valgrind options" FORCE)
       set(VALGRIND_COMMAND_OPTIONS "${MEMORYCHECK_COMMAND_OPTIONS}" CACHE STRING "Valgrind options" FORCE)
     endif()
@@ -467,7 +467,7 @@ endif()
 #           ####   #          #       #     ####   #    #   ####
 #
 
-set(MDBX_BUILD_OPTIONS ENABLE_UBSAN ENABLE_ASAN MDBX_USE_VALGRIND ENABLE_GPROF ENABLE_GCOV)
+set(MDBX_BUILD_OPTIONS ENABLE_UBSAN ENABLE_ASAN ENABLE_MEMCHECK ENABLE_GPROF ENABLE_GCOV)
 macro(add_mdbx_option NAME DESCRIPTION DEFAULT)
   list(APPEND MDBX_BUILD_OPTIONS ${NAME})
   if(NOT ${DEFAULT} STREQUAL "AUTO")
@@ -531,6 +531,8 @@ add_mdbx_option(MDBX_ENABLE_BIGFOOT "Chunking long list of retired pages during
 add_mdbx_option(MDBX_ENABLE_PGOP_STAT "Gathering statistics for page operations" ON)
 add_mdbx_option(MDBX_ENABLE_PROFGC "Profiling of GC search and updates" OFF)
 mark_as_advanced(MDBX_ENABLE_PROFGC)
+add_mdbx_option(MDBX_ENABLE_DBI_SPARSE "FIXME" ON)
+add_mdbx_option(MDBX_ENABLE_DBI_LOCKFREE "FIXME" ON)
 
 if(NOT MDBX_AMALGAMATED_SOURCE)
   if(CMAKE_CONFIGURATION_TYPES OR CMAKE_BUILD_TYPE_UPPERCASE STREQUAL "DEBUG")

ChangeLog.md

@@ -4,6 +4,67 @@ ChangeLog
 English version [by Google](https://gitflic-ru.translate.goog/project/erthink/libmdbx/blob?file=ChangeLog.md&_x_tr_sl=ru&_x_tr_tl=en)
 and [by Yandex](https://translated.turbopages.org/proxy_u/ru-en.en/https/gitflic.ru/project/erthink/libmdbx/blob?file=ChangeLog.md).
 
+## v0.13.1 (в процессе подготовки релиза)
+
+Новая версия с существенным расширением API и добавлением функционала.
+
+Новое:
+
+ - Управление основной блокировкой lock/unlock/upgrade/downgrade для координации пишущих транзакций.
+ - `mdbx_env_chk() `для проверка целостности структуры БД, с переработкой и переносом функционала утилиты `mdbx_chk` внутрь библиотеки.
+ - `mdbx_dbi_rename()` и `mdbx_dbi_rename()` для переименования таблиц.
+ - `mdbx_cursor_unbind()` и `mdbx_txn_release_all_cursors()` для управления курсорами.
+ - `mdbx_env_resurrect_after_fork()` для восстановление открытой среды работы с БД в дочернем процессе после ветвления/расщепления процесса.
+ - `mdbx_cursor_compare()` для сравнения позиций курсоров.
+ - `mdbx_cursor_scan()` и `mdbx_cursor_scan_from()` для сканирования таблиц с использованием функционального предиката.
+ - `mdbx_cursor_on_first_dup()` и `mdbx_cursor_on_last_dup()` для проверки позиции курсора.
+ - `mdbx_preopen_snapinfo()` для получения информации о БД без её открытия.
+
+ - Расширение и доработка C++ API:
+
+     - добавлен тип `mdbx::cursor::estimation_result`, а поведение методов
+      `cursor::estimate()` унифицировано с `cursor::move()`;
+     - для предотвращения незаметного неверного использования API, для инициализации
+       возвращаемых по ссылке срезов, вместо пустых срезов задействован `slice::invalid()`;
+     - добавлены дополнительные C++ операторы преобразования к типам C API;
+     - для совместимости со старыми стандартами C++ и старыми версиями STL перенесены
+       в public классы `buffer::move_assign_alloc` и `buffer::copy_assign_alloc`;
+     - добавлен тип `mdbx::default_buffer`;
+     - для срезов и буферов добавлены методы `hex_decode()`, `base64_decode()`, `base58_decode()`;
+     - добавлен тип `mdbx::comparator` и функций `mdbx::default_comparator()`;
+     - добавлены статические методы `buffer::hex()`, `base64()`, `base58()`;
+     - для транзакций и курсоров добавлены методы `get_/set_context`;
+     - добавлен метод `cursor::clone()`;
+     - поддержка base58 переработана и приведена в соответствии с черновиком RFC, в текущем понимании теперь это одна из самых высокопроизводительных реализаций;
+     - переработка `to_hex()` и `from_hex()`.
+
+
+## v0.13.0 от 2023-04-23
+
+Не выпуск, а начало ветки `0.13` с новым функционалом и изменением API.
+
+Новое:
+
+ - Расширение API функционалом проверки целостности структуры БД, с
+   переработкой и переноса функционала утилиты `mdbx_chk` внутрь библиотеки.
+
+ - Расширение API функциями lock/unlock/upgrade/downgrade основной блокировки.
+
+ - Добавление в API функций `mdbx_cursor_unbind()` и `mdbx_txn_release_all_cursors()`.
+
+ - Возвращение `MDBX_TXN_INVALID` (`INT32_MIN`) вместо `-1`
+   из `mdbx_txn_flags()` при передаче невалидной транзакции.
+
+Мелочи:
+
+ - Обновление конфигурации Doxygen до 1.9.6.
+ - Добавление `--read-var-info=yes` для Valgrind.
+ - Вывод из `mdbx_chk` информации об уровне детализации/verbosity.
+
+
+********************************************************************************
+
+
 ## v0.12.10 "СЭМ" от 2024-03-12
 
 Поддерживающий выпуск с исправлением обнаруженных ошибок и устранением недочетов
@@ -152,6 +213,7 @@ Signed-off-by: Леонид Юрьев (Leonid Yuriev) <leo@yuriev.ru>
 
 ## v0.12.8 "Владимир Уткин" от 2023-10-17
 
+
 Стабилизирующий выпуск с исправлением обнаруженных ошибок и устранением недочетов,
 в день 100-летия со дня рождения выдающегося советского и российского ученого и конструктора [Влади́мира Фёдоровича У́ткина](https://ru.wikipedia.org/wiki/Уткин,_Владимир_Фёдорович).
 

GNUmakefile

@@ -172,22 +172,22 @@ help:
 	@echo "  make bench-clean         - remove temp database(s) after benchmark"
 #> dist-cutoff-begin
 	@echo ""
-	@echo "  make smoke               - fast smoke test"
-	@echo "  make test                - basic test"
 	@echo "  make check               - smoke test with amalgamation and installation checking"
-	@echo "  make long-test           - execute long test which runs for several weeks, or until you interrupt it"
+	@echo "  make smoke               - fast smoke test"
-	@echo "  make memcheck            - build with Valgrind's and smoke test with memcheck tool"
+	@echo "  make smoke-memcheck      - build with Valgrind support and run smoke test under memcheck tool"
-	@echo "  make test-valgrind       - build with Valgrind's and basic test with memcheck tool"
+	@echo "  make smoke-fault         - execute transaction owner failure smoke testcase"
-	@echo "  make test-asan           - build with AddressSanitizer and basic test"
+	@echo "  make smoke-singleprocess - execute single-process smoke test"
-	@echo "  make test-leak           - build with LeakSanitizer and basic test"
+	@echo "  make test                - basic test"
-	@echo "  make test-ubsan          - build with UndefinedBehaviourSanitizer and basic test"
+	@echo "  make test-memcheck       - build with Valgrind support and run basic test under memcheck tool"
+	@echo "  make test-long           - execute long test which runs for several weeks, or until interruption"
+	@echo "  make test-asan           - build with AddressSanitizer and run basic test"
+	@echo "  make test-leak           - build with LeakSanitizer and run basic test"
+	@echo "  make test-ubsan          - build with UndefinedBehaviourSanitizer and run basic test"
+	@echo "  make test-singleprocess  - execute single-process basic test (also used by make cross-qemu)"
 	@echo "  make cross-gcc           - check cross-compilation without test execution"
 	@echo "  make cross-qemu          - run cross-compilation and execution basic test with QEMU"
 	@echo "  make gcc-analyzer        - run gcc-analyzer (mostly useless for now)"
 	@echo "  make build-test          - build test executable(s)"
-	@echo "  make smoke-fault         - execute transaction owner failure smoke testcase"
-	@echo "  make smoke-singleprocess - execute single-process smoke test"
-	@echo "  make test-singleprocess  - execute single-process basic test (also used by make cross-qemu)"
 	@echo ""
 	@echo "  make dist                - build amalgamated source code"
 	@echo "  make doxygen             - build HTML documentation"
@@ -328,8 +328,14 @@ else
 
 .PHONY: build-test build-test-with-valgrind check cross-gcc cross-qemu dist doxygen gcc-analyzer long-test
 .PHONY: reformat release-assets tags smoke test test-asan smoke-fault test-leak
-.PHONY: smoke-singleprocess test-singleprocess test-ubsan test-valgrind memcheck
+.PHONY: smoke-singleprocess test-singleprocess test-ubsan test-valgrind test-memcheck memcheck smoke-memcheck
-.PHONY: smoke-assertion test-assertion long-test-assertion
+.PHONY: smoke-assertion test-assertion long-test-assertion test-ci test-ci-extra
+
+test-ci-extra: test-ci cross-gcc cross-qemu
+
+test-ci: check \
+	smoke-singleprocess smoke-fault smoke-memcheck smoke \
+	test-leak test-asan test-ubsan test-singleprocess test test-memcheck
 
 define uname2osal
   case "$(UNAME)" in
@@ -418,27 +424,30 @@ smoke-fault: build-test
 
 test: build-test
 	@echo '  RUNNING `test/long_stochastic.sh --loops 2`...'
-	$(QUIET)test/long_stochastic.sh --dont-check-ram-size --loops 2 --db-upto-mb 256 --skip-make >$(TEST_LOG) || (cat $(TEST_LOG) && false)
+	$(QUIET)test/long_stochastic.sh --dont-check-ram-size --loops 2 --db-upto-mb 256 --extra --skip-make --taillog >$(TEST_LOG) || (cat $(TEST_LOG) && false)
 
-long-test: build-test
+long-test: test-long
+test-long: build-test
 	@echo '  RUNNING `test/long_stochastic.sh --loops 42`...'
-	$(QUIET)test/long_stochastic.sh --loops 42 --db-upto-mb 1024 --skip-make
+	$(QUIET)test/long_stochastic.sh --loops 42 --db-upto-mb 1024 --extra --skip-make --taillog
 
 test-singleprocess: build-test
 	@echo '  RUNNING `test/long_stochastic.sh --single --loops 2`...'
-	$(QUIET)test/long_stochastic.sh --dont-check-ram-size --single --loops 2 --db-upto-mb 256 --skip-make >$(TEST_LOG) || (cat $(TEST_LOG) && false)
+	$(QUIET)test/long_stochastic.sh --dont-check-ram-size --single --loops 2 --db-upto-mb 256 --skip-make --taillog >$(TEST_LOG) || (cat $(TEST_LOG) && false)
 
-test-valgrind: CFLAGS_EXTRA=-Ofast -DMDBX_USE_VALGRIND
+test-valgrind: test-memcheck
-test-valgrind: build-test
+test-memcheck: CFLAGS_EXTRA=-Ofast -DENABLE_MEMCHECK
+test-memcheck: build-test
 	@echo '  RUNNING `test/long_stochastic.sh --with-valgrind --loops 2`...'
-	$(QUIET)test/long_stochastic.sh --with-valgrind --loops 2 --db-upto-mb 256 --skip-make >$(TEST_LOG) || (cat $(TEST_LOG) && false)
+	$(QUIET)test/long_stochastic.sh --with-valgrind --extra --loops 2 --db-upto-mb 256 --skip-make >$(TEST_LOG) || (cat $(TEST_LOG) && false)
 
-memcheck: VALGRIND=valgrind --trace-children=yes --log-file=valgrind-%p.log --leak-check=full --track-origins=yes --error-exitcode=42 --suppressions=test/valgrind_suppress.txt
+memcheck: smoke-memcheck
-memcheck: CFLAGS_EXTRA=-Ofast -DMDBX_USE_VALGRIND
+smoke-memcheck: VALGRIND=valgrind --trace-children=yes --log-file=valgrind-%p.log --leak-check=full --track-origins=yes --read-var-info=yes --error-exitcode=42 --suppressions=test/valgrind_suppress.txt
-memcheck: build-test
+smoke-memcheck: CFLAGS_EXTRA=-Ofast -DENABLE_MEMCHECK
+smoke-memcheck: build-test
 	@echo "  SMOKE \`mdbx_test basic\` under Valgrind's memcheck..."
 	$(QUIET)rm -f valgrind-*.log $(TEST_DB) $(TEST_LOG).gz && (set -o pipefail; ( \
-		$(VALGRIND) ./mdbx_test --table=+data.integer --keygen.split=29 --datalen.min=min --datalen.max=max --progress --console=no --repeat=2 --pathname=$(TEST_DB) --dont-cleanup-after $(MDBX_SMOKE_EXTRA) basic && \
+		$(VALGRIND) ./mdbx_test --table=+data.fixed --keygen.split=29 --datalen=35 --progress --console=no --repeat=2 --pathname=$(TEST_DB) --dont-cleanup-after $(MDBX_SMOKE_EXTRA) basic && \
 		$(VALGRIND) ./mdbx_test --progress --console=no --pathname=$(TEST_DB) --dont-cleanup-before --dont-cleanup-after --copy && \
 		$(VALGRIND) ./mdbx_test --mode=-writemap,-nosync-safe,-lifo --progress --console=no --repeat=4 --pathname=$(TEST_DB) --dont-cleanup-after $(MDBX_SMOKE_EXTRA) basic && \
 		$(VALGRIND) ./mdbx_chk -vvn $(TEST_DB) && \

Makefile

@@ -6,9 +6,10 @@ bench bench-clean bench-couple bench-quartet bench-triplet re-bench \
 lib libs lib-static lib-shared tools-static \
 libmdbx mdbx mdbx_chk mdbx_copy mdbx_drop mdbx_dump mdbx_load mdbx_stat \
 check dist memcheck cross-gcc cross-qemu doxygen gcc-analyzer reformat \
-release-assets tags test build-test mdbx_test smoke smoke-fault smoke-singleprocess \
+release-assets tags build-test mdbx_test \
-smoke-assertion test-assertion long-test-assertion \
+smoke smoke-fault smoke-singleprocess smoke-assertion smoke-memcheck \
-test-asan test-leak test-singleprocess test-ubsan test-valgrind:
+test test-assertion test-long test-long-assertion test-ci test-ci-extra \
+test-asan test-leak test-singleprocess test-ubsan test-memcheck:
 	@CC=$(CC) \
 	CXX=`if test -n "$(CXX)" && which "$(CXX)" > /dev/null; then echo "$(CXX)"; elif test -n "$(CCC)" && which "$(CCC)" > /dev/null; then echo "$(CCC)"; else echo "c++"; fi` \
 	`which gmake || which gnumake || echo 'echo "GNU Make 3.80 or above is required"; exit 2;'` \

TODO.md

@@ -11,7 +11,6 @@ For the same reason ~~Github~~ is blacklisted forever.
 
 So currently most of the links are broken due to noted malicious ~~Github~~ sabotage.
 
- - [Move most of `mdbx_chk` functional to the library API](https://libmdbx.dqdkfa.ru/dead-github/issues/204).
  - [Replace SRW-lock on Windows to allow shrink DB with `MDBX_NOTLS` option](https://libmdbx.dqdkfa.ru/dead-github/issues/210).
  - [More flexible support of asynchronous runtime/framework(s)](https://libmdbx.dqdkfa.ru/dead-github/issues/200).
  - [Migration guide from LMDB to MDBX](https://libmdbx.dqdkfa.ru/dead-github/issues/199).
@@ -23,6 +22,7 @@ So currently most of the links are broken due to noted malicious ~~Github~~ sabo
 Done
 ----
 
+ - [Move most of `mdbx_chk` functional to the library API](https://libmdbx.dqdkfa.ru/dead-github/issues/204).
  - [Simple careful mode for working with corrupted DB](https://libmdbx.dqdkfa.ru/dead-github/issues/223).
  - [Engage an "overlapped I/O" on Windows](https://libmdbx.dqdkfa.ru/dead-github/issues/224).
  - [Large/Overflow pages accounting for dirty-room](https://libmdbx.dqdkfa.ru/dead-github/issues/192).

cmake/profile.cmake

@@ -24,6 +24,25 @@ endif()
 cmake_policy(PUSH)
 cmake_policy(VERSION ${CMAKE_MINIMUM_REQUIRED_VERSION})
 
+unset(MEMCHECK_OPTION_NAME)
+if(NOT DEFINED ENABLE_MEMCHECK)
+  if (DEFINED MDBX_USE_VALGRIND)
+    set(MEMCHECK_OPTION_NAME "MDBX_USE_VALGRIND")
+  elseif(DEFINED ENABLE_VALGRIND)
+    set(MEMCHECK_OPTION_NAME "ENABLE_VALGRIND")
+  else()
+    set(MEMCHECK_OPTION_NAME "ENABLE_MEMCHECK")
+  endif()
+  if(MEMCHECK_OPTION_NAME STREQUAL "ENABLE_MEMCHECK")
+    option(ENABLE_MEMCHECK
+      "Enable integration with valgrind, a memory analyzing tool" OFF)
+  elseif(${MEMCHECK_OPTION_NAME})
+    set(ENABLE_MEMCHECK ON)
+  else()
+    set(ENABLE_MEMCHECK OFF)
+  endif()
+endif()
+
 include(CheckLibraryExists)
 check_library_exists(gcov __gcov_flush "" HAVE_GCOV)
 
@@ -33,23 +52,23 @@ option(ENABLE_GCOV
 option(ENABLE_GPROF
   "Enable integration with gprof, a performance analyzing tool" OFF)
 
-if(CMAKE_CXX_COMPILER_LOADED)
-  include(CheckIncludeFileCXX)
-  check_include_file_cxx(valgrind/memcheck.h HAVE_VALGRIND_MEMCHECK_H)
-else()
-  include(CheckIncludeFile)
-  check_include_file(valgrind/memcheck.h HAVE_VALGRIND_MEMCHECK_H)
-endif()
-
-option(MDBX_USE_VALGRIND "Enable integration with valgrind, a memory analyzing tool" OFF)
-if(MDBX_USE_VALGRIND AND NOT HAVE_VALGRIND_MEMCHECK_H)
-  message(FATAL_ERROR "MDBX_USE_VALGRIND option is set but valgrind/memcheck.h is not found")
-endif()
-
 option(ENABLE_ASAN
   "Enable AddressSanitizer, a fast memory error detector based on compiler instrumentation" OFF)
 
 option(ENABLE_UBSAN
   "Enable UndefinedBehaviorSanitizer, a fast undefined behavior detector based on compiler instrumentation" OFF)
 
+if(ENABLE_MEMCHECK)
+  if(CMAKE_CXX_COMPILER_LOADED)
+    include(CheckIncludeFileCXX)
+    check_include_file_cxx(valgrind/memcheck.h HAVE_VALGRIND_MEMCHECK_H)
+  else()
+    include(CheckIncludeFile)
+    check_include_file(valgrind/memcheck.h HAVE_VALGRIND_MEMCHECK_H)
+  endif()
+  if(NOT HAVE_VALGRIND_MEMCHECK_H)
+    message(FATAL_ERROR "${MEMCHECK_OPTION_NAME} option is set but valgrind/memcheck.h is not found")
+  endif()
+endif()
+
 cmake_policy(POP)

docs/Doxyfile.in

@@ -1,4 +1,4 @@
-# Doxyfile 1.9.1
+# Doxyfile 1.9.6
 
 # This file describes the settings to be used by the documentation system
 # doxygen (www.doxygen.org) for a project.
@@ -12,6 +12,16 @@
 # For lists, items can also be appended using:
 # TAG += value [value, ...]
 # Values that contain spaces should be placed between quotes (\" \").
+#
+# Note:
+#
+# Use doxygen to compare the used configuration file with the template
+# configuration file:
+# doxygen -x [configFile]
+# Use doxygen to compare the used configuration file with the template
+# configuration file without replacing the environment variables or CMake type
+# replacement variables:
+# doxygen -x_noenv [configFile]
 
 #---------------------------------------------------------------------------
 # Project related configuration options
@@ -60,16 +70,28 @@ PROJECT_LOGO           =
 
 OUTPUT_DIRECTORY       = .
 
-# If the CREATE_SUBDIRS tag is set to YES then doxygen will create 4096 sub-
+# If the CREATE_SUBDIRS tag is set to YES then doxygen will create up to 4096
-# directories (in 2 levels) under the output directory of each output format and
+# sub-directories (in 2 levels) under the output directory of each output format
-# will distribute the generated files over these directories. Enabling this
+# and will distribute the generated files over these directories. Enabling this
 # option can be useful when feeding doxygen a huge amount of source files, where
 # putting all generated files in the same directory would otherwise causes
-# performance problems for the file system.
+# performance problems for the file system. Adapt CREATE_SUBDIRS_LEVEL to
+# control the number of sub-directories.
 # The default value is: NO.
 
 CREATE_SUBDIRS         = NO
 
+# Controls the number of sub-directories that will be created when
+# CREATE_SUBDIRS tag is set to YES. Level 0 represents 16 directories, and every
+# level increment doubles the number of directories, resulting in 4096
+# directories at level 8 which is the default and also the maximum value. The
+# sub-directories are organized in 2 levels, the first level always has a fixed
+# number of 16 directories.
+# Minimum value: 0, maximum value: 8, default value: 8.
+# This tag requires that the tag CREATE_SUBDIRS is set to YES.
+
+CREATE_SUBDIRS_LEVEL   = 8
+
 # If the ALLOW_UNICODE_NAMES tag is set to YES, doxygen will allow non-ASCII
 # characters to appear in the names of generated files. If set to NO, non-ASCII
 # characters will be escaped, for example _xE3_x81_x84 will be used for Unicode
@@ -81,26 +103,18 @@ ALLOW_UNICODE_NAMES    = NO
 # The OUTPUT_LANGUAGE tag is used to specify the language in which all
 # documentation generated by doxygen is written. Doxygen will use this
 # information to generate all constant output in the proper language.
-# Possible values are: Afrikaans, Arabic, Armenian, Brazilian, Catalan, Chinese,
+# Possible values are: Afrikaans, Arabic, Armenian, Brazilian, Bulgarian,
-# Chinese-Traditional, Croatian, Czech, Danish, Dutch, English (United States),
+# Catalan, Chinese, Chinese-Traditional, Croatian, Czech, Danish, Dutch, English
-# Esperanto, Farsi (Persian), Finnish, French, German, Greek, Hungarian,
+# (United States), Esperanto, Farsi (Persian), Finnish, French, German, Greek,
-# Indonesian, Italian, Japanese, Japanese-en (Japanese with English messages),
+# Hindi, Hungarian, Indonesian, Italian, Japanese, Japanese-en (Japanese with
-# Korean, Korean-en (Korean with English messages), Latvian, Lithuanian,
+# English messages), Korean, Korean-en (Korean with English messages), Latvian,
-# Macedonian, Norwegian, Persian (Farsi), Polish, Portuguese, Romanian, Russian,
+# Lithuanian, Macedonian, Norwegian, Persian (Farsi), Polish, Portuguese,
-# Serbian, Serbian-Cyrillic, Slovak, Slovene, Spanish, Swedish, Turkish,
+# Romanian, Russian, Serbian, Serbian-Cyrillic, Slovak, Slovene, Spanish,
-# Ukrainian and Vietnamese.
+# Swedish, Turkish, Ukrainian and Vietnamese.
 # The default value is: English.
 
 OUTPUT_LANGUAGE        = English
 
-# The OUTPUT_TEXT_DIRECTION tag is used to specify the direction in which all
-# documentation generated by doxygen is written. Doxygen will use this
-# information to generate all generated output in the proper direction.
-# Possible values are: None, LTR, RTL and Context.
-# The default value is: None.
-
-OUTPUT_TEXT_DIRECTION  = None
-
 # If the BRIEF_MEMBER_DESC tag is set to YES, doxygen will include brief member
 # descriptions after the members that are listed in the file and class
 # documentation (similar to Javadoc). Set to NO to disable this.
@@ -258,16 +272,16 @@ TAB_SIZE               = 4
 # the documentation. An alias has the form:
 # name=value
 # For example adding
-# "sideeffect=@par Side Effects:\n"
+# "sideeffect=@par Side Effects:^^"
 # will allow you to put the command \sideeffect (or @sideeffect) in the
 # documentation, which will result in a user-defined paragraph with heading
-# "Side Effects:". You can put \n's in the value part of an alias to insert
+# "Side Effects:". Note that you cannot put \n's in the value part of an alias
-# newlines (in the resulting output). You can put ^^ in the value part of an
+# to insert newlines (in the resulting output). You can put ^^ in the value part
-# alias to insert a newline as if a physical newline was in the original file.
+# of an alias to insert a newline as if a physical newline was in the original
-# When you need a literal { or } or , in the value part of an alias you have to
+# file. When you need a literal { or } or , in the value part of an alias you
-# escape them by means of a backslash (\), this can lead to conflicts with the
+# have to escape them by means of a backslash (\), this can lead to conflicts
-# commands \{ and \} for these it is advised to use the version @{ and @} or use
+# with the commands \{ and \} for these it is advised to use the version @{ and
-# a double escape (\\{ and \\})
+# @} or use a double escape (\\{ and \\})
 
 ALIASES                =
 
@@ -312,8 +326,8 @@ OPTIMIZE_OUTPUT_SLICE  = NO
 # extension. Doxygen has a built-in mapping, but you can override or extend it
 # using this tag. The format is ext=language, where ext is a file extension, and
 # language is one of the parsers supported by doxygen: IDL, Java, JavaScript,
-# Csharp (C#), C, C++, D, PHP, md (Markdown), Objective-C, Python, Slice, VHDL,
+# Csharp (C#), C, C++, Lex, D, PHP, md (Markdown), Objective-C, Python, Slice,
-# Fortran (fixed format Fortran: FortranFixed, free formatted Fortran:
+# VHDL, Fortran (fixed format Fortran: FortranFixed, free formatted Fortran:
 # FortranFree, unknown formatted Fortran: Fortran. In the later case the parser
 # tries to guess whether the code is fixed or free formatted code, this is the
 # default for Fortran type files). For instance to make doxygen treat .inc files
@@ -460,13 +474,13 @@ TYPEDEF_HIDES_STRUCT   = YES
 
 LOOKUP_CACHE_SIZE      = 0
 
-# The NUM_PROC_THREADS specifies the number threads doxygen is allowed to use
+# The NUM_PROC_THREADS specifies the number of threads doxygen is allowed to use
 # during processing. When set to 0 doxygen will based this on the number of
 # cores available in the system. You can set it explicitly to a value larger
 # than 0 to get more control over the balance between CPU load and processing
 # speed. At this moment only the input processing can be done using multiple
 # threads. Since this is still an experimental feature the default is set to 1,
-# which efficively disables parallel processing. Please report any issues you
+# which effectively disables parallel processing. Please report any issues you
 # encounter. Generating dot graphs in parallel is controlled by the
 # DOT_NUM_THREADS setting.
 # Minimum value: 0, maximum value: 32, default value: 1.
@@ -554,7 +568,8 @@ HIDE_UNDOC_MEMBERS     = NO
 # If the HIDE_UNDOC_CLASSES tag is set to YES, doxygen will hide all
 # undocumented classes that are normally visible in the class hierarchy. If set
 # to NO, these classes will be included in the various overviews. This option
-# has no effect if EXTRACT_ALL is enabled.
+# will also hide undocumented C++ concepts if enabled. This option has no effect
+# if EXTRACT_ALL is enabled.
 # The default value is: NO.
 
 HIDE_UNDOC_CLASSES     = NO
@@ -585,14 +600,15 @@ INTERNAL_DOCS          = NO
 # filesystem is case sensitive (i.e. it supports files in the same directory
 # whose names only differ in casing), the option must be set to YES to properly
 # deal with such files in case they appear in the input. For filesystems that
-# are not case sensitive the option should be be set to NO to properly deal with
+# are not case sensitive the option should be set to NO to properly deal with
 # output files written for symbols that only differ in casing, such as for two
 # classes, one named CLASS and the other named Class, and to also support
 # references to files without having to specify the exact matching casing. On
 # Windows (including Cygwin) and MacOS, users should typically set this option
 # to NO, whereas on Linux or other Unix flavors it should typically be set to
 # YES.
-# The default value is: system dependent.
+# Possible values are: SYSTEM, NO and YES.
+# The default value is: SYSTEM.
 
 CASE_SENSE_NAMES       = NO
 
@@ -610,6 +626,12 @@ HIDE_SCOPE_NAMES       = NO
 
 HIDE_COMPOUND_REFERENCE= NO
 
+# If the SHOW_HEADERFILE tag is set to YES then the documentation for a class
+# will show which file needs to be included to use the class.
+# The default value is: YES.
+
+SHOW_HEADERFILE        = YES
+
 # If the SHOW_INCLUDE_FILES tag is set to YES then doxygen will put a list of
 # the files that are included by a file in the documentation of that file.
 # The default value is: YES.
@@ -767,7 +789,8 @@ FILE_VERSION_FILTER    =
 # output files in an output format independent way. To create the layout file
 # that represents doxygen's defaults, run doxygen with the -l option. You can
 # optionally specify a file name after the option, if omitted DoxygenLayout.xml
-# will be used as the name of the layout file.
+# will be used as the name of the layout file. See also section "Changing the
+# layout of pages" for information.
 #
 # Note that if you run doxygen from a directory containing a file called
 # DoxygenLayout.xml, doxygen will parse it automatically even if the LAYOUT_FILE
@@ -813,22 +836,38 @@ WARNINGS               = YES
 WARN_IF_UNDOCUMENTED   = YES
 
 # If the WARN_IF_DOC_ERROR tag is set to YES, doxygen will generate warnings for
-# potential errors in the documentation, such as not documenting some parameters
+# potential errors in the documentation, such as documenting some parameters in
-# in a documented function, or documenting parameters that don't exist or using
+# a documented function twice, or documenting parameters that don't exist or
-# markup commands wrongly.
+# using markup commands wrongly.
 # The default value is: YES.
 
 WARN_IF_DOC_ERROR      = YES
 
+# If WARN_IF_INCOMPLETE_DOC is set to YES, doxygen will warn about incomplete
+# function parameter documentation. If set to NO, doxygen will accept that some
+# parameters have no documentation without warning.
+# The default value is: YES.
+
+WARN_IF_INCOMPLETE_DOC = YES
+
 # This WARN_NO_PARAMDOC option can be enabled to get warnings for functions that
 # are documented, but have no documentation for their parameters or return
-# value. If set to NO, doxygen will only warn about wrong or incomplete
+# value. If set to NO, doxygen will only warn about wrong parameter
-# parameter documentation, but not about the absence of documentation. If
+# documentation, but not about the absence of documentation. If EXTRACT_ALL is
-# EXTRACT_ALL is set to YES then this flag will automatically be disabled.
+# set to YES then this flag will automatically be disabled. See also
+# WARN_IF_INCOMPLETE_DOC
 # The default value is: NO.
 
 WARN_NO_PARAMDOC       = NO
 
+# If WARN_IF_UNDOC_ENUM_VAL option is set to YES, doxygen will warn about
+# undocumented enumeration values. If set to NO, doxygen will accept
+# undocumented enumeration values. If EXTRACT_ALL is set to YES then this flag
+# will automatically be disabled.
+# The default value is: NO.
+
+WARN_IF_UNDOC_ENUM_VAL = NO
+
 # If the WARN_AS_ERROR tag is set to YES then doxygen will immediately stop when
 # a warning is encountered. If the WARN_AS_ERROR tag is set to FAIL_ON_WARNINGS
 # then doxygen will continue running as if WARN_AS_ERROR tag is set to NO, but
@@ -844,13 +883,27 @@ WARN_AS_ERROR          = NO
 # and the warning text. Optionally the format may contain $version, which will
 # be replaced by the version of the file (if it could be obtained via
 # FILE_VERSION_FILTER)
+# See also: WARN_LINE_FORMAT
 # The default value is: $file:$line: $text.
 
 WARN_FORMAT            = "$file:$line: $text"
 
+# In the $text part of the WARN_FORMAT command it is possible that a reference
+# to a more specific place is given. To make it easier to jump to this place
+# (outside of doxygen) the user can define a custom "cut" / "paste" string.
+# Example:
+# WARN_LINE_FORMAT = "'vi $file +$line'"
+# See also: WARN_FORMAT
+# The default value is: at line $line of file $file.
+
+WARN_LINE_FORMAT       = "at line $line of file $file"
+
 # The WARN_LOGFILE tag can be used to specify a file to which warning and error
 # messages should be written. If left blank the output is written to standard
-# error (stderr).
+# error (stderr). In case the file specified cannot be opened for writing the
+# warning and error messages are written to standard error. When as file - is
+# specified the warning and error messages are written to standard output
+# (stdout).
 
 WARN_LOGFILE           =
 
@@ -877,10 +930,21 @@ INPUT                  = overall.md \
 # libiconv (or the iconv built into libc) for the transcoding. See the libiconv
 # documentation (see:
 # https://www.gnu.org/software/libiconv/) for the list of possible encodings.
+# See also: INPUT_FILE_ENCODING
 # The default value is: UTF-8.
 
 INPUT_ENCODING         = UTF-8
 
+# This tag can be used to specify the character encoding of the source files
+# that doxygen parses The INPUT_FILE_ENCODING tag can be used to specify
+# character encoding on a per file pattern basis. Doxygen will compare the file
+# name with each pattern and apply the encoding instead of the default
+# INPUT_ENCODING) if there is a match. The character encodings are a list of the
+# form: pattern=encoding (like *.php=ISO-8859-1). See cfg_input_encoding
+# "INPUT_ENCODING" for further information on supported encodings.
+
+INPUT_FILE_ENCODING    =
+
 # If the value of the INPUT tag contains directories, you can use the
 # FILE_PATTERNS tag to specify one or more wildcard patterns (like *.cpp and
 # *.h) to filter out the source-files in the directories.
@@ -894,10 +958,10 @@ INPUT_ENCODING         = UTF-8
 #
 # If left blank the following patterns are tested:*.c, *.cc, *.cxx, *.cpp,
 # *.c++, *.java, *.ii, *.ixx, *.ipp, *.i++, *.inl, *.idl, *.ddl, *.odl, *.h,
-# *.hh, *.hxx, *.hpp, *.h++, *.cs, *.d, *.php, *.php4, *.php5, *.phtml, *.inc,
+# *.hh, *.hxx, *.hpp, *.h++, *.l, *.cs, *.d, *.php, *.php4, *.php5, *.phtml,
-# *.m, *.markdown, *.md, *.mm, *.dox (to be provided as doxygen C comment),
+# *.inc, *.m, *.markdown, *.md, *.mm, *.dox (to be provided as doxygen C
-# *.py, *.pyw, *.f90, *.f95, *.f03, *.f08, *.f18, *.f, *.for, *.vhd, *.vhdl,
+# comment), *.py, *.pyw, *.f90, *.f95, *.f03, *.f08, *.f18, *.f, *.for, *.vhd,
-# *.ucf, *.qsf and *.ice.
+# *.vhdl, *.ucf, *.qsf and *.ice.
 
 FILE_PATTERNS          = *.h
 
@@ -936,20 +1000,40 @@ EXCLUDE_PATTERNS       =
 # (namespaces, classes, functions, etc.) that should be excluded from the
 # output. The symbol name can be a fully qualified name, a word, or if the
 # wildcard * is used, a substring. Examples: ANamespace, AClass,
-# AClass::ANamespace, ANamespace::*Test
+# ANamespace::AClass, ANamespace::*Test
 #
 # Note that the wildcards are matched against the file with absolute path, so to
 # exclude all test directories use the pattern */test/*
 
-EXCLUDE_SYMBOLS        = NOMINMAX __ORDER_BIG_ENDIAN__ __ORDER_LITTLE_ENDIAN__ \
+EXCLUDE_SYMBOLS        = NOMINMAX \
-	 __has_include __has_attribute __has_builtin __has_cpp_attribute __has_extension __has_feature \
+                         __ORDER_BIG_ENDIAN__ \
-	HAVE_STRUCT_IOVEC MDBX_STRINGIFY_HELPER MDBX_STRINGIFY \
+                         __ORDER_LITTLE_ENDIAN__ \
-	MDBX_NOSANITIZE_ENUM MDBX_PRINTF_ARGS \
+                         __has_include \
-	MDBX_HAVE_CXX20_CONCEPTS \
+                         __has_attribute \
-	CONSTEXPR_ENUM_FLAGS_OPERATIONS DEFINE_ENUM_FLAG_OPERATORS \
+                         __has_builtin \
-	bool false true __dll_export __dll_import \
+                         __has_cpp_attribute \
-	MDBX_64BIT_ATOMIC_CONFIG MDBX_64BIT_CAS_CONFIG MDBX_ENV_CHECKPID_CONFIG MDBX_LOCKING_CONFIG \
+                         __has_extension \
-	MDBX_TRUST_RTC_CONFIG MDBX_TXN_CHECKOWNER_CONFIG MDBX_USE_OFDLOCKS_CONFIG
+                         __has_feature \
+                         HAVE_STRUCT_IOVEC \
+                         MDBX_STRINGIFY_HELPER \
+                         MDBX_STRINGIFY \
+                         MDBX_NOSANITIZE_ENUM \
+                         MDBX_PRINTF_ARGS \
+                         MDBX_HAVE_CXX20_CONCEPTS \
+                         CONSTEXPR_ENUM_FLAGS_OPERATIONS \
+                         DEFINE_ENUM_FLAG_OPERATORS \
+                         bool \
+                         false \
+                         true \
+                         __dll_export \
+                         __dll_import \
+                         MDBX_64BIT_ATOMIC_CONFIG \
+                         MDBX_64BIT_CAS_CONFIG \
+                         MDBX_ENV_CHECKPID_CONFIG \
+                         MDBX_LOCKING_CONFIG \
+                         MDBX_TRUST_RTC_CONFIG \
+                         MDBX_TXN_CHECKOWNER_CONFIG \
+                         MDBX_USE_OFDLOCKS_CONFIG
 
 # The EXAMPLE_PATH tag can be used to specify one or more files or directories
 # that contain example code fragments that are included (see the \include
@@ -992,6 +1076,11 @@ IMAGE_PATH             =
 # code is scanned, but not when the output code is generated. If lines are added
 # or removed, the anchors will not be placed correctly.
 #
+# Note that doxygen will use the data processed and written to standard output
+# for further processing, therefore nothing else, like debug statements or used
+# commands (so in case of a Windows batch file always use @echo OFF), should be
+# written to standard output.
+#
 # Note that for custom extensions or not directly supported extensions you also
 # need to set EXTENSION_MAPPING for the extension otherwise the files are not
 # properly processed by doxygen.
@@ -1033,6 +1122,15 @@ FILTER_SOURCE_PATTERNS =
 
 USE_MDFILE_AS_MAINPAGE =
 
+# The Fortran standard specifies that for fixed formatted Fortran code all
+# characters from position 72 are to be considered as comment. A common
+# extension is to allow longer lines before the automatic comment starts. The
+# setting FORTRAN_COMMENT_AFTER will also make it possible that longer lines can
+# be processed before the automatic comment starts.
+# Minimum value: 7, maximum value: 10000, default value: 72.
+
+FORTRAN_COMMENT_AFTER  = 72
+
 #---------------------------------------------------------------------------
 # Configuration options related to source browsing
 #---------------------------------------------------------------------------
@@ -1130,9 +1228,11 @@ VERBATIM_HEADERS       = YES
 
 CLANG_ASSISTED_PARSING = NO
 
-# If clang assisted parsing is enabled and the CLANG_ADD_INC_PATHS tag is set to
+# If the CLANG_ASSISTED_PARSING tag is set to YES and the CLANG_ADD_INC_PATHS
-# YES then doxygen will add the directory of each input to the include path.
+# tag is set to YES then doxygen will add the directory of each input to the
+# include path.
 # The default value is: YES.
+# This tag requires that the tag CLANG_ASSISTED_PARSING is set to YES.
 
 CLANG_ADD_INC_PATHS    = YES
 
@@ -1168,10 +1268,11 @@ CLANG_DATABASE_PATH    =
 
 ALPHABETICAL_INDEX     = YES
 
-# In case all classes in a project start with a common prefix, all classes will
+# The IGNORE_PREFIX tag can be used to specify a prefix (or a list of prefixes)
-# be put under the same header in the alphabetical index. The IGNORE_PREFIX tag
+# that should be ignored while generating the index headers. The IGNORE_PREFIX
-# can be used to specify a prefix (or a list of prefixes) that should be ignored
+# tag works for classes, function and member names. The entity will be placed in
-# while generating the index headers.
+# the alphabetical list under the first letter of the entity name that remains
+# after removing the prefix.
 # This tag requires that the tag ALPHABETICAL_INDEX is set to YES.
 
 IGNORE_PREFIX          =
@@ -1250,7 +1351,12 @@ HTML_STYLESHEET        =
 # Doxygen will copy the style sheet files to the output directory.
 # Note: The order of the extra style sheet files is of importance (e.g. the last
 # style sheet in the list overrules the setting of the previous ones in the
-# list). For an example see the documentation.
+# list).
+# Note: Since the styling of scrollbars can currently not be overruled in
+# Webkit/Chromium, the styling will be left out of the default doxygen.css if
+# one or more extra stylesheets have been specified. So if scrollbar
+# customization is desired it has to be added explicitly. For an example see the
+# documentation.
 # This tag requires that the tag GENERATE_HTML is set to YES.
 
 HTML_EXTRA_STYLESHEET  =
@@ -1265,9 +1371,22 @@ HTML_EXTRA_STYLESHEET  =
 
 HTML_EXTRA_FILES       =
 
+# The HTML_COLORSTYLE tag can be used to specify if the generated HTML output
+# should be rendered with a dark or light theme.
+# Possible values are: LIGHT always generate light mode output, DARK always
+# generate dark mode output, AUTO_LIGHT automatically set the mode according to
+# the user preference, use light mode if no preference is set (the default),
+# AUTO_DARK automatically set the mode according to the user preference, use
+# dark mode if no preference is set and TOGGLE allow to user to switch between
+# light and dark mode via a button.
+# The default value is: AUTO_LIGHT.
+# This tag requires that the tag GENERATE_HTML is set to YES.
+
+HTML_COLORSTYLE        = AUTO_LIGHT
+
 # The HTML_COLORSTYLE_HUE tag controls the color of the HTML output. Doxygen
 # will adjust the colors in the style sheet and background images according to
-# this color. Hue is specified as an angle on a colorwheel, see
+# this color. Hue is specified as an angle on a color-wheel, see
 # https://en.wikipedia.org/wiki/Hue for more information. For instance the value
 # 0 represents red, 60 is yellow, 120 is green, 180 is cyan, 240 is blue, 300
 # purple, and 360 is red again.
@@ -1277,7 +1396,7 @@ HTML_EXTRA_FILES       =
 HTML_COLORSTYLE_HUE    = 220
 
 # The HTML_COLORSTYLE_SAT tag controls the purity (or saturation) of the colors
-# in the HTML output. For a value of 0 the output will use grayscales only. A
+# in the HTML output. For a value of 0 the output will use gray-scales only. A
 # value of 255 will produce the most vivid colors.
 # Minimum value: 0, maximum value: 255, default value: 100.
 # This tag requires that the tag GENERATE_HTML is set to YES.
@@ -1359,6 +1478,13 @@ GENERATE_DOCSET        = NO
 
 DOCSET_FEEDNAME        = "Doxygen generated docs"
 
+# This tag determines the URL of the docset feed. A documentation feed provides
+# an umbrella under which multiple documentation sets from a single provider
+# (such as a company or product suite) can be grouped.
+# This tag requires that the tag GENERATE_DOCSET is set to YES.
+
+DOCSET_FEEDURL         =
+
 # This tag specifies a string that should uniquely identify the documentation
 # set bundle. This should be a reverse domain-name style string, e.g.
 # com.mycompany.MyDocSet. Doxygen will append .docset to the name.
@@ -1384,8 +1510,12 @@ DOCSET_PUBLISHER_NAME  = Publisher
 # If the GENERATE_HTMLHELP tag is set to YES then doxygen generates three
 # additional HTML index files: index.hhp, index.hhc, and index.hhk. The
 # index.hhp is a project file that can be read by Microsoft's HTML Help Workshop
-# (see:
+# on Windows. In the beginning of 2021 Microsoft took the original page, with
-# https://www.microsoft.com/en-us/download/details.aspx?id=21138) on Windows.
+# a.o. the download links, offline the HTML help workshop was already many years
+# in maintenance mode). You can download the HTML help workshop from the web
+# archives at Installation executable (see:
+# http://web.archive.org/web/20160201063255/http://download.microsoft.com/downlo
+# ad/0/A/9/0A939EF6-E31C-430F-A3DF-DFAE7960D564/htmlhelp.exe).
 #
 # The HTML Help Workshop contains a compiler that can convert all HTML output
 # generated by doxygen into a single compiled HTML file (.chm). Compiled HTML
@@ -1544,16 +1674,28 @@ DISABLE_INDEX          = YES
 # to work a browser that supports JavaScript, DHTML, CSS and frames is required
 # (i.e. any modern browser). Windows users are probably better off using the
 # HTML help feature. Via custom style sheets (see HTML_EXTRA_STYLESHEET) one can
-# further fine-tune the look of the index. As an example, the default style
+# further fine tune the look of the index (see "Fine-tuning the output"). As an
-# sheet generated by doxygen has an example that shows how to put an image at
+# example, the default style sheet generated by doxygen has an example that
-# the root of the tree instead of the PROJECT_NAME. Since the tree basically has
+# shows how to put an image at the root of the tree instead of the PROJECT_NAME.
-# the same information as the tab index, you could consider setting
+# Since the tree basically has the same information as the tab index, you could
-# DISABLE_INDEX to YES when enabling this option.
+# consider setting DISABLE_INDEX to YES when enabling this option.
 # The default value is: NO.
 # This tag requires that the tag GENERATE_HTML is set to YES.
 
 GENERATE_TREEVIEW      = YES
 
+# When both GENERATE_TREEVIEW and DISABLE_INDEX are set to YES, then the
+# FULL_SIDEBAR option determines if the side bar is limited to only the treeview
+# area (value NO) or if it should extend to the full height of the window (value
+# YES). Setting this to YES gives a layout similar to
+# https://docs.readthedocs.io with more room for contents, but less room for the
+# project logo, title, and description. If either GENERATE_TREEVIEW or
+# DISABLE_INDEX is set to NO, this option has no effect.
+# The default value is: NO.
+# This tag requires that the tag GENERATE_HTML is set to YES.
+
+FULL_SIDEBAR           = NO
+
 # The ENUM_VALUES_PER_LINE tag can be used to set the number of enum values that
 # doxygen will group on one line in the generated HTML documentation.
 #
@@ -1578,6 +1720,13 @@ TREEVIEW_WIDTH         = 250
 
 EXT_LINKS_IN_WINDOW    = NO
 
+# If the OBFUSCATE_EMAILS tag is set to YES, doxygen will obfuscate email
+# addresses.
+# The default value is: YES.
+# This tag requires that the tag GENERATE_HTML is set to YES.
+
+OBFUSCATE_EMAILS       = YES
+
 # If the HTML_FORMULA_FORMAT option is set to svg, doxygen will use the pdf2svg
 # tool (see https://github.com/dawbarton/pdf2svg) or inkscape (see
 # https://inkscape.org) to generate formulas as SVG images instead of PNGs for
@@ -1598,17 +1747,6 @@ HTML_FORMULA_FORMAT    = png
 
 FORMULA_FONTSIZE       = 10
 
-# Use the FORMULA_TRANSPARENT tag to determine whether or not the images
-# generated for formulas are transparent PNGs. Transparent PNGs are not
-# supported properly for IE 6.0, but are supported on all modern browsers.
-#
-# Note that when changing this option you need to delete any form_*.png files in
-# the HTML output directory before the changes have effect.
-# The default value is: YES.
-# This tag requires that the tag GENERATE_HTML is set to YES.
-
-FORMULA_TRANSPARENT    = YES
-
 # The FORMULA_MACROFILE can contain LaTeX \newcommand and \renewcommand commands
 # to create new LaTeX commands to be used in formulas as building blocks. See
 # the section "Including formulas" for details.
@@ -1626,11 +1764,29 @@ FORMULA_MACROFILE      =
 
 USE_MATHJAX            = YES
 
+# With MATHJAX_VERSION it is possible to specify the MathJax version to be used.
+# Note that the different versions of MathJax have different requirements with
+# regards to the different settings, so it is possible that also other MathJax
+# settings have to be changed when switching between the different MathJax
+# versions.
+# Possible values are: MathJax_2 and MathJax_3.
+# The default value is: MathJax_2.
+# This tag requires that the tag USE_MATHJAX is set to YES.
+
+MATHJAX_VERSION        = MathJax_2
+
 # When MathJax is enabled you can set the default output format to be used for
-# the MathJax output. See the MathJax site (see:
+# the MathJax output. For more details about the output format see MathJax
-# http://docs.mathjax.org/en/v2.7-latest/output.html) for more details.
+# version 2 (see:
+# http://docs.mathjax.org/en/v2.7-latest/output.html) and MathJax version 3
+# (see:
+# http://docs.mathjax.org/en/latest/web/components/output.html).
 # Possible values are: HTML-CSS (which is slower, but has the best
-# compatibility), NativeMML (i.e. MathML) and SVG.
+# compatibility. This is the name for Mathjax version 2, for MathJax version 3
+# this will be translated into chtml), NativeMML (i.e. MathML. Only supported
+# for NathJax 2. For MathJax version 3 chtml will be used instead.), chtml (This
+# is the name for Mathjax version 3, for MathJax version 2 this will be
+# translated into HTML-CSS) and SVG.
 # The default value is: HTML-CSS.
 # This tag requires that the tag USE_MATHJAX is set to YES.
 
@@ -1643,15 +1799,21 @@ MATHJAX_FORMAT         = HTML-CSS
 # MATHJAX_RELPATH should be ../mathjax. The default value points to the MathJax
 # Content Delivery Network so you can quickly see the result without installing
 # MathJax. However, it is strongly recommended to install a local copy of
-# MathJax from https://www.mathjax.org before deployment.
+# MathJax from https://www.mathjax.org before deployment. The default value is:
-# The default value is: https://cdn.jsdelivr.net/npm/mathjax@2.
+# - in case of MathJax version 2: https://cdn.jsdelivr.net/npm/mathjax@2
+# - in case of MathJax version 3: https://cdn.jsdelivr.net/npm/mathjax@3
 # This tag requires that the tag USE_MATHJAX is set to YES.
 
 MATHJAX_RELPATH        = https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/
 
 # The MATHJAX_EXTENSIONS tag can be used to specify one or more MathJax
 # extension names that should be enabled during MathJax rendering. For example
+# for MathJax version 2 (see
+# https://docs.mathjax.org/en/v2.7-latest/tex.html#tex-and-latex-extensions):
 # MATHJAX_EXTENSIONS = TeX/AMSmath TeX/AMSsymbols
+# For example for MathJax version 3 (see
+# http://docs.mathjax.org/en/latest/input/tex/extensions/index.html):
+# MATHJAX_EXTENSIONS = ams
 # This tag requires that the tag USE_MATHJAX is set to YES.
 
 MATHJAX_EXTENSIONS     =
@@ -1831,29 +1993,31 @@ PAPER_TYPE             = a4
 
 EXTRA_PACKAGES         =
 
-# The LATEX_HEADER tag can be used to specify a personal LaTeX header for the
+# The LATEX_HEADER tag can be used to specify a user-defined LaTeX header for
-# generated LaTeX document. The header should contain everything until the first
+# the generated LaTeX document. The header should contain everything until the
-# chapter. If it is left blank doxygen will generate a standard header. See
+# first chapter. If it is left blank doxygen will generate a standard header. It
-# section "Doxygen usage" for information on how to let doxygen write the
+# is highly recommended to start with a default header using
-# default header to a separate file.
+# doxygen -w latex new_header.tex new_footer.tex new_stylesheet.sty
+# and then modify the file new_header.tex. See also section "Doxygen usage" for
+# information on how to generate the default header that doxygen normally uses.
 #
-# Note: Only use a user-defined header if you know what you are doing! The
+# Note: Only use a user-defined header if you know what you are doing!
-# following commands have a special meaning inside the header: $title,
+# Note: The header is subject to change so you typically have to regenerate the
-# $datetime, $date, $doxygenversion, $projectname, $projectnumber,
+# default header when upgrading to a newer version of doxygen. The following
-# $projectbrief, $projectlogo. Doxygen will replace $title with the empty
+# commands have a special meaning inside the header (and footer): For a
-# string, for the replacement values of the other commands the user is referred
+# description of the possible markers and block names see the documentation.
-# to HTML_HEADER.
 # This tag requires that the tag GENERATE_LATEX is set to YES.
 
 LATEX_HEADER           =
 
-# The LATEX_FOOTER tag can be used to specify a personal LaTeX footer for the
+# The LATEX_FOOTER tag can be used to specify a user-defined LaTeX footer for
-# generated LaTeX document. The footer should contain everything after the last
+# the generated LaTeX document. The footer should contain everything after the
-# chapter. If it is left blank doxygen will generate a standard footer. See
+# last chapter. If it is left blank doxygen will generate a standard footer. See
 # LATEX_HEADER for more information on how to generate a default footer and what
-# special commands can be used inside the footer.
+# special commands can be used inside the footer. See also section "Doxygen
-#
+# usage" for information on how to generate the default footer that doxygen
-# Note: Only use a user-defined footer if you know what you are doing!
+# normally uses. Note: Only use a user-defined footer if you know what you are
+# doing!
 # This tag requires that the tag GENERATE_LATEX is set to YES.
 
 LATEX_FOOTER           =
@@ -1898,8 +2062,7 @@ USE_PDFLATEX           = YES
 
 # If the LATEX_BATCHMODE tag is set to YES, doxygen will add the \batchmode
 # command to the generated LaTeX files. This will instruct LaTeX to keep running
-# if errors occur, instead of asking the user for help. This option is also used
+# if errors occur, instead of asking the user for help.
-# when generating formulas in HTML.
 # The default value is: NO.
 # This tag requires that the tag GENERATE_LATEX is set to YES.
 
@@ -1912,16 +2075,6 @@ LATEX_BATCHMODE        = NO
 
 LATEX_HIDE_INDICES     = NO
 
-# If the LATEX_SOURCE_CODE tag is set to YES then doxygen will include source
-# code with syntax highlighting in the LaTeX output.
-#
-# Note that which sources are shown also depends on other settings such as
-# SOURCE_BROWSER.
-# The default value is: NO.
-# This tag requires that the tag GENERATE_LATEX is set to YES.
-
-LATEX_SOURCE_CODE      = NO
-
 # The LATEX_BIB_STYLE tag can be used to specify the style to use for the
 # bibliography, e.g. plainnat, or ieeetr. See
 # https://en.wikipedia.org/wiki/BibTeX and \cite for more info.
@@ -2002,16 +2155,6 @@ RTF_STYLESHEET_FILE    =
 
 RTF_EXTENSIONS_FILE    =
 
-# If the RTF_SOURCE_CODE tag is set to YES then doxygen will include source code
-# with syntax highlighting in the RTF output.
-#
-# Note that which sources are shown also depends on other settings such as
-# SOURCE_BROWSER.
-# The default value is: NO.
-# This tag requires that the tag GENERATE_RTF is set to YES.
-
-RTF_SOURCE_CODE        = NO
-
 #---------------------------------------------------------------------------
 # Configuration options related to the man page output
 #---------------------------------------------------------------------------
@@ -2108,15 +2251,6 @@ GENERATE_DOCBOOK       = NO
 
 DOCBOOK_OUTPUT         = docbook
 
-# If the DOCBOOK_PROGRAMLISTING tag is set to YES, doxygen will include the
-# program listings (including syntax highlighting and cross-referencing
-# information) to the DOCBOOK output. Note that enabling this will significantly
-# increase the size of the DOCBOOK output.
-# The default value is: NO.
-# This tag requires that the tag GENERATE_DOCBOOK is set to YES.
-
-DOCBOOK_PROGRAMLISTING = NO
-
 #---------------------------------------------------------------------------
 # Configuration options for the AutoGen Definitions output
 #---------------------------------------------------------------------------
@@ -2203,7 +2337,8 @@ SEARCH_INCLUDES        = YES
 
 # The INCLUDE_PATH tag can be used to specify one or more directories that
 # contain include files that are not input files but should be processed by the
-# preprocessor.
+# preprocessor. Note that the INCLUDE_PATH is not recursive, so the setting of
+# RECURSIVE has no effect here.
 # This tag requires that the tag SEARCH_INCLUDES is set to YES.
 
 INCLUDE_PATH           =
@@ -2224,24 +2359,30 @@ INCLUDE_FILE_PATTERNS  =
 # recursively expanded use the := operator instead of the = operator.
 # This tag requires that the tag ENABLE_PREPROCESSING is set to YES.
 
-
 PREDEFINED             = DOXYGEN \
-	MDBX_CXX20_CONCEPT(CONCEPT,NAME)="CONCEPT NAME" \
+                         "MDBX_CXX20_CONCEPT(CONCEPT,NAME)=CONCEPT NAME" \
-	MDBX_STD_FILESYSTEM_PATH=::mdbx::filesystem::path \
+                         MDBX_STD_FILESYSTEM_PATH=::mdbx::filesystem::path \
-	MDBX_U128_TYPE=uint128_t MDBX_I128_TYPE=int128_t \
+                         MDBX_U128_TYPE=uint128_t \
-	MDBX_DECLARE_EXCEPTION(NAME)="struct LIBMDBX_API_TYPE NAME : public exception{NAME(const ::mdbx::error &); virtual ~NAME() noexcept; }" \
+                         MDBX_I128_TYPE=int128_t \
-	MDBX_PURE_FUNCTION=[[gnu::pure]] \
+                         "MDBX_DECLARE_EXCEPTION(NAME)=struct LIBMDBX_API_TYPE NAME : public exception{NAME(const ::mdbx::error &); virtual ~NAME() noexcept; }" \
-	MDBX_NOTHROW_PURE_FUNCTION="[[gnu::pure, gnu::nothrow]]" \
+                         MDBX_PURE_FUNCTION=[[gnu::pure]] \
-	MDBX_CONST_FUNCTION=[[gnu::const]] \
+                         "MDBX_NOTHROW_PURE_FUNCTION=[[gnu::pure, gnu::nothrow]]" \
-	MDBX_NOTHROW_CONST_FUNCTION="[[gnu::const, gnu::nothrow]]" \
+                         MDBX_CONST_FUNCTION=[[gnu::const]] \
-	MDBX_CXX01_CONSTEXPR=constexpr MDBX_CXX01_CONSTEXPR_VAR=constexpr \
+                         "MDBX_NOTHROW_CONST_FUNCTION=[[gnu::const, gnu::nothrow]]" \
-	MDBX_CXX11_CONSTEXPR=constexpr MDBX_CXX11_CONSTEXPR_VAR=constexpr \
+                         MDBX_CXX01_CONSTEXPR=constexpr \
-	MDBX_CXX14_CONSTEXPR=constexpr MDBX_CXX14_CONSTEXPR_VAR=constexpr \
+                         MDBX_CXX01_CONSTEXPR_VAR=constexpr \
-	MDBX_CXX17_CONSTEXPR=constexpr MDBX_CXX20_CONSTEXPR=constexpr \
+                         MDBX_CXX11_CONSTEXPR=constexpr \
-	MDBX_CXX17_NOEXCEPT=noexcept MDBX_IF_CONSTEXPR=constexpr \
+                         MDBX_CXX11_CONSTEXPR_VAR=constexpr \
-	MDBX_CXX20_LIKELY=[[likely]] MDBX_CXX20_UNLIKELY=[[unlikely]] \
+                         MDBX_CXX14_CONSTEXPR=constexpr \
-	MDBX_MAYBE_UNUSED=[[maybe_unused]] \
+                         MDBX_CXX14_CONSTEXPR_VAR=constexpr \
-	MDBX_DEPRECATED=[[deprecated]]
+                         MDBX_CXX17_CONSTEXPR=constexpr \
+                         MDBX_CXX20_CONSTEXPR=constexpr \
+                         MDBX_CXX17_NOEXCEPT=noexcept \
+                         MDBX_IF_CONSTEXPR=constexpr \
+                         MDBX_CXX20_LIKELY=[[likely]] \
+                         MDBX_CXX20_UNLIKELY=[[unlikely]] \
+                         MDBX_MAYBE_UNUSED=[[maybe_unused]] \
+                         MDBX_DEPRECATED=[[deprecated]]
 
 # If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then this
 # tag can be used to specify a list of macro names that should be expanded. The
@@ -2312,15 +2453,6 @@ EXTERNAL_PAGES         = NO
 # Configuration options related to the dot tool
 #---------------------------------------------------------------------------
 
-# If the CLASS_DIAGRAMS tag is set to YES, doxygen will generate a class diagram
-# (in HTML and LaTeX) for classes with base or super classes. Setting the tag to
-# NO turns the diagrams off. Note that this option also works with HAVE_DOT
-# disabled, but it is recommended to install and use dot, since it yields more
-# powerful graphs.
-# The default value is: YES.
-
-CLASS_DIAGRAMS         = NO
-
 # You can include diagrams made with dia in doxygen documentation. Doxygen will
 # then run dia to produce the diagram and insert it in the documentation. The
 # DIA_PATH tag allows you to specify the directory where the dia binary resides.
@@ -2339,7 +2471,7 @@ HIDE_UNDOC_RELATIONS   = YES
 # http://www.graphviz.org/), a graph visualization toolkit from AT&T and Lucent
 # Bell Labs. The other options in this section have no effect if this option is
 # set to NO
-# The default value is: YES.
+# The default value is: NO.
 
 HAVE_DOT               = NO
 
@@ -2353,37 +2485,52 @@ HAVE_DOT               = NO
 
 DOT_NUM_THREADS        = 0
 
-# When you want a differently looking font in the dot files that doxygen
+# DOT_COMMON_ATTR is common attributes for nodes, edges and labels of
-# generates you can specify the font name using DOT_FONTNAME. You need to make
+# subgraphs. When you want a differently looking font in the dot files that
-# sure dot is able to find the font, which can be done by putting it in a
+# doxygen generates you can specify fontname, fontcolor and fontsize attributes.
-# standard location or by setting the DOTFONTPATH environment variable or by
+# For details please see <a href=https://graphviz.org/doc/info/attrs.html>Node,
-# setting DOT_FONTPATH to the directory containing the font.
+# Edge and Graph Attributes specification</a> You need to make sure dot is able
-# The default value is: Helvetica.
+# to find the font, which can be done by putting it in a standard location or by
+# setting the DOTFONTPATH environment variable or by setting DOT_FONTPATH to the
+# directory containing the font. Default graphviz fontsize is 14.
+# The default value is: fontname=Helvetica,fontsize=10.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-DOT_FONTNAME           = Helvetica
+DOT_COMMON_ATTR        = "fontname=Helvetica,fontsize=10"
 
-# The DOT_FONTSIZE tag can be used to set the size (in points) of the font of
+# DOT_EDGE_ATTR is concatenated with DOT_COMMON_ATTR. For elegant style you can
-# dot graphs.
+# add 'arrowhead=open, arrowtail=open, arrowsize=0.5'. <a
-# Minimum value: 4, maximum value: 24, default value: 10.
+# href=https://graphviz.org/doc/info/arrows.html>Complete documentation about
+# arrows shapes.</a>
+# The default value is: labelfontname=Helvetica,labelfontsize=10.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-DOT_FONTSIZE           = 10
+DOT_EDGE_ATTR          = "labelfontname=Helvetica,labelfontsize=10"
 
-# By default doxygen will tell dot to use the default font as specified with
+# DOT_NODE_ATTR is concatenated with DOT_COMMON_ATTR. For view without boxes
-# DOT_FONTNAME. If you specify a different font using DOT_FONTNAME you can set
+# around nodes set 'shape=plain' or 'shape=plaintext' <a
-# the path where dot can find it using this tag.
+# href=https://www.graphviz.org/doc/info/shapes.html>Shapes specification</a>
+# The default value is: shape=box,height=0.2,width=0.4.
+# This tag requires that the tag HAVE_DOT is set to YES.
+
+DOT_NODE_ATTR          = "shape=box,height=0.2,width=0.4"
+
+# You can set the path where dot can find font specified with fontname in
+# DOT_COMMON_ATTR and others dot attributes.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
 DOT_FONTPATH           =
 
-# If the CLASS_GRAPH tag is set to YES then doxygen will generate a graph for
+# If the CLASS_GRAPH tag is set to YES (or GRAPH) then doxygen will generate a
-# each documented class showing the direct and indirect inheritance relations.
+# graph for each documented class showing the direct and indirect inheritance
-# Setting this tag to YES will force the CLASS_DIAGRAMS tag to NO.
+# relations. In case HAVE_DOT is set as well dot will be used to draw the graph,
+# otherwise the built-in generator will be used. If the CLASS_GRAPH tag is set
+# to TEXT the direct and indirect inheritance relations will be shown as texts /
+# links.
+# Possible values are: NO, YES, TEXT and GRAPH.
 # The default value is: YES.
-# This tag requires that the tag HAVE_DOT is set to YES.
 
-CLASS_GRAPH            = YES
+CLASS_GRAPH            = TEXT
 
 # If the COLLABORATION_GRAPH tag is set to YES then doxygen will generate a
 # graph for each documented class showing the direct and indirect implementation
@@ -2395,7 +2542,8 @@ CLASS_GRAPH            = YES
 COLLABORATION_GRAPH    = YES
 
 # If the GROUP_GRAPHS tag is set to YES then doxygen will generate a graph for
-# groups, showing the direct groups dependencies.
+# groups, showing the direct groups dependencies. See also the chapter Grouping
+# in the manual.
 # The default value is: YES.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
@@ -2510,6 +2658,13 @@ GRAPHICAL_HIERARCHY    = YES
 
 DIRECTORY_GRAPH        = YES
 
+# The DIR_GRAPH_MAX_DEPTH tag can be used to limit the maximum number of levels
+# of child directories generated in directory dependency graphs by dot.
+# Minimum value: 1, maximum value: 25, default value: 1.
+# This tag requires that the tag DIRECTORY_GRAPH is set to YES.
+
+DIR_GRAPH_MAX_DEPTH    = 1
+
 # The DOT_IMAGE_FORMAT tag can be used to set the image format of the images
 # generated by dot. For an explanation of the image formats see the section
 # output formats in the documentation of the dot tool (Graphviz (see:
@@ -2517,9 +2672,7 @@ DIRECTORY_GRAPH        = YES
 # Note: If you choose svg you need to set HTML_FILE_EXTENSION to xhtml in order
 # to make the SVG files visible in IE 9+ (other browsers do not have this
 # requirement).
-# Possible values are: png, png:cairo, png:cairo:cairo, png:cairo:gd, png:gd,
+# Possible values are: png, jpg, gif, svg, png:gd, png:gd:gd, png:cairo,
-# png:gd:gd, jpg, jpg:cairo, jpg:cairo:gd, jpg:gd, jpg:gd:gd, gif, gif:cairo,
-# gif:cairo:gd, gif:gd, gif:gd:gd, svg, png:gd, png:gd:gd, png:cairo,
 # png:cairo:gd, png:cairo:cairo, png:cairo:gdiplus, png:gdiplus and
 # png:gdiplus:gdiplus.
 # The default value is: png.
@@ -2565,10 +2718,10 @@ MSCFILE_DIRS           =
 DIAFILE_DIRS           =
 
 # When using plantuml, the PLANTUML_JAR_PATH tag should be used to specify the
-# path where java can find the plantuml.jar file. If left blank, it is assumed
+# path where java can find the plantuml.jar file or to the filename of jar file
-# PlantUML is not used or called during a preprocessing step. Doxygen will
+# to be used. If left blank, it is assumed PlantUML is not used or called during
-# generate a warning when it encounters a \startuml command in this case and
+# a preprocessing step. Doxygen will generate a warning when it encounters a
-# will not generate output for the diagram.
+# \startuml command in this case and will not generate output for the diagram.
 
 PLANTUML_JAR_PATH      =
 
@@ -2606,18 +2759,6 @@ DOT_GRAPH_MAX_NODES    = 50
 
 MAX_DOT_GRAPH_DEPTH    = 0
 
-# Set the DOT_TRANSPARENT tag to YES to generate images with a transparent
-# background. This is disabled by default, because dot on Windows does not seem
-# to support this out of the box.
-#
-# Warning: Depending on the platform used, enabling this option may lead to
-# badly anti-aliased labels on the edges of a graph (i.e. they become hard to
-# read).
-# The default value is: NO.
-# This tag requires that the tag HAVE_DOT is set to YES.
-
-DOT_TRANSPARENT        = NO
-
 # Set the DOT_MULTI_TARGETS tag to YES to allow dot to generate multiple output
 # files in one run (i.e. multiple -o and -T options on the command line). This
 # makes dot run faster, but since only newer versions of dot (>1.8.10) support
@@ -2630,6 +2771,8 @@ DOT_MULTI_TARGETS      = NO
 # If the GENERATE_LEGEND tag is set to YES doxygen will generate a legend page
 # explaining the meaning of the various boxes and arrows in the dot generated
 # graphs.
+# Note: This tag requires that UML_LOOK isn't set, i.e. the doxygen internal
+# graphical representation for inheritance and collaboration diagrams is used.
 # The default value is: YES.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
@@ -2638,8 +2781,8 @@ GENERATE_LEGEND        = YES
 # If the DOT_CLEANUP tag is set to YES, doxygen will remove the intermediate
 # files that are used to generate the various graphs.
 #
-# Note: This setting is not only used for dot files but also for msc and
+# Note: This setting is not only used for dot files but also for msc temporary
-# plantuml temporary files.
+# files.
 # The default value is: YES.
 
 DOT_CLEANUP            = YES

docs/_restrictions.md

@@ -106,6 +106,7 @@ reservation can deplete system resources (trigger ENOMEM error, etc)
 when setting an inadequately large upper DB size using \ref
 mdbx_env_set_geometry() or \ref mdbx::env::geometry. So just avoid this.
 
+
 ## Remote filesystems
 Do not use MDBX databases on remote filesystems, even between processes
 on the same host. This breaks file locks on some platforms, possibly
@@ -132,6 +133,11 @@ corruption in such cases.
 On the other hand, MDBX allow calling \ref mdbx_env_close() in such cases to
 release resources, but no more and in general this is a wrong way.
 
+#### Since v0.13.1 and later
+Начиная с версии 0.13.1 в API доступна функция \ref mdbx_env_resurrect_after_fork(),
+которая позволяет пере-использовать в дочерних процессах уже открытую среду БД,
+но строго без наследования транзакций от родительского процесса.
+
 
 ## Read-only mode
 There is no pure read-only mode in a normal explicitly way, since

mdbx.h

@@ -634,9 +634,9 @@ typedef mode_t mdbx_mode_t;
 extern "C" {
 #endif
 
-/* MDBX version 0.12.x */
+/* MDBX version 0.13.x */
 #define MDBX_VERSION_MAJOR 0
-#define MDBX_VERSION_MINOR 12
+#define MDBX_VERSION_MINOR 13
 
 #ifndef LIBMDBX_API
 #if defined(LIBMDBX_EXPORTS)
@@ -816,7 +816,7 @@ typedef struct iovec MDBX_val;
 #endif /* ! SunOS */
 
 enum MDBX_constants {
-  /** The hard limit for DBI handles */
+  /** The hard limit for DBI handles. */
   MDBX_MAX_DBI = UINT32_C(32765),
 
   /** The maximum size of a data item. */
@@ -1778,7 +1778,7 @@ enum MDBX_cursor_op {
    * return both key and data, and the return code depends on whether a
    * upper-bound was found.
    *
-   * For non DUPSORT-ed collections this work the same to \ref MDBX_SET_RANGE,
+   * For non DUPSORT-ed collections this work like \ref MDBX_SET_RANGE,
    * but returns \ref MDBX_SUCCESS if the greater key was found or
    * \ref MDBX_NOTFOUND otherwise.
    *
@@ -1786,7 +1786,28 @@ enum MDBX_cursor_op {
    * i.e. for a pairs/tuples of a key and an each data value of duplicates.
    * Returns \ref MDBX_SUCCESS if the greater pair was returned or
    * \ref MDBX_NOTFOUND otherwise. */
-  MDBX_SET_UPPERBOUND
+  MDBX_SET_UPPERBOUND,
+
+  /* Doubtless cursor positioning at a specified key. */
+  MDBX_TO_KEY_LESSER_THAN,
+  MDBX_TO_KEY_LESSER_OR_EQUAL,
+  MDBX_TO_KEY_EQUAL,
+  MDBX_TO_KEY_GREATER_OR_EQUAL,
+  MDBX_TO_KEY_GREATER_THAN,
+
+  /* Doubtless cursor positioning at a specified key-value pair
+   * for dupsort/multi-value hives. */
+  MDBX_TO_EXACT_KEY_VALUE_LESSER_THAN,
+  MDBX_TO_EXACT_KEY_VALUE_LESSER_OR_EQUAL,
+  MDBX_TO_EXACT_KEY_VALUE_EQUAL,
+  MDBX_TO_EXACT_KEY_VALUE_GREATER_OR_EQUAL,
+  MDBX_TO_EXACT_KEY_VALUE_GREATER_THAN,
+
+  MDBX_TO_PAIR_LESSER_THAN,
+  MDBX_TO_PAIR_LESSER_OR_EQUAL,
+  MDBX_TO_PAIR_EQUAL,
+  MDBX_TO_PAIR_GREATER_OR_EQUAL,
+  MDBX_TO_PAIR_GREATER_THAN
 };
 #ifndef __cplusplus
 /** \ingroup c_cursors */
@@ -1921,7 +1942,7 @@ enum MDBX_error_t {
   MDBX_TOO_LARGE = -30417,
 
   /** A thread has attempted to use a not owned object,
-   * e.g. a transaction that started by another thread. */
+   * e.g. a transaction that started by another thread */
   MDBX_THREAD_MISMATCH = -30416,
 
   /** Overlapping read and write transactions for the current thread */
@@ -1936,8 +1957,12 @@ enum MDBX_error_t {
   /** Alternative/Duplicate LCK-file is exists and should be removed manually */
   MDBX_DUPLICATED_CLK = -30413,
 
+  /** Some cursors and/or other resources should be closed before subDb or
+   *  corresponding DBI-handle could be (re)used */
+  MDBX_DANGLING_DBI = -30412,
+
   /* The last of MDBX-added error codes */
-  MDBX_LAST_ADDED_ERRCODE = MDBX_DUPLICATED_CLK,
+  MDBX_LAST_ADDED_ERRCODE = MDBX_DANGLING_DBI,
 
 #if defined(_WIN32) || defined(_WIN64)
   MDBX_ENODATA = ERROR_HANDLE_EOF,
@@ -1950,7 +1975,8 @@ enum MDBX_error_t {
   MDBX_EPERM = ERROR_INVALID_FUNCTION,
   MDBX_EINTR = ERROR_CANCELLED,
   MDBX_ENOFILE = ERROR_FILE_NOT_FOUND,
-  MDBX_EREMOTE = ERROR_REMOTE_STORAGE_MEDIA_ERROR
+  MDBX_EREMOTE = ERROR_REMOTE_STORAGE_MEDIA_ERROR,
+  MDBX_EDEADLK = ERROR_POSSIBLE_DEADLOCK
 #else /* Windows */
 #ifdef ENODATA
   MDBX_ENODATA = ENODATA,
@@ -1966,7 +1992,8 @@ enum MDBX_error_t {
   MDBX_EPERM = EPERM,
   MDBX_EINTR = EINTR,
   MDBX_ENOFILE = ENOENT,
-  MDBX_EREMOTE = ENOTBLK
+  MDBX_EREMOTE = ENOTBLK,
+  MDBX_EDEADLK = EDEADLK
 #endif /* !Windows */
 };
 #ifndef __cplusplus
@@ -2106,6 +2133,7 @@ enum MDBX_option_t {
   /** \brief Controls the in-process limit to grow a list of reclaimed/recycled
    * page's numbers for finding a sequence of contiguous pages for large data
    * items.
+   * \see MDBX_opt_gc_time_limit
    *
    * \details A long values requires allocation of contiguous database pages.
    * To find such sequences, it may be necessary to accumulate very large lists,
@@ -2266,6 +2294,33 @@ enum MDBX_option_t {
    * in the \ref MDBX_WRITEMAP mode by clearing ones through file handle before
    * touching. */
   MDBX_opt_prefault_write_enable,
+
+  /** \brief Controls the in-process spending time limit of searching
+   *  consecutive pages inside GC.
+   * \see MDBX_opt_rp_augment_limit
+   *
+   * \details Задаёт ограничение времени в 1/65536 долях секунды, которое может
+   * быть потрачено в ходе пишущей транзакции на поиск последовательностей
+   * страниц внутри GC/freelist после достижения ограничения задаваемого опцией
+   * \ref MDBX_opt_rp_augment_limit. Контроль по времени не выполняется при
+   * поиске/выделении одиночных страниц и выделении страниц под нужды GC (при
+   * обновлении GC в ходе фиксации транзакции).
+   *
+   * Задаваемый лимит времени исчисляется по "настенным часам" и контролируется
+   * в рамках транзакции, наследуется для вложенных транзакций и с
+   * аккумулированием в родительской при их фиксации. Контроль по времени
+   * производится только при достижении ограничения задаваемого опцией \ref
+   * MDBX_opt_rp_augment_limit. Это позволяет гибко управлять поведением
+   * используя обе опции.
+   *
+   * По умолчанию ограничение устанавливается в 0, что приводит к
+   * незамедлительной остановке поиска в GC при достижении \ref
+   * MDBX_opt_rp_augment_limit во внутреннем состоянии транзакции и
+   * соответствует поведению до появления опции `MDBX_opt_gc_time_limit`.
+   * С другой стороны, при минимальном значении (включая 0)
+   * `MDBX_opt_rp_augment_limit` переработка GC будет ограничиваться
+   * преимущественно затраченным временем. */
+  MDBX_opt_gc_time_limit
 };
 #ifndef __cplusplus
 /** \ingroup c_settings */
@@ -2571,9 +2626,7 @@ struct MDBX_envinfo {
   uint64_t mi_latter_reader_txnid; /**< ID of the last reader transaction */
   uint64_t mi_self_latter_reader_txnid; /**< ID of the last reader transaction
                                            of caller process */
-  uint64_t mi_meta0_txnid, mi_meta0_sign;
+  uint64_t mi_meta_txnid[3], mi_meta_sign[3];
-  uint64_t mi_meta1_txnid, mi_meta1_sign;
-  uint64_t mi_meta2_txnid, mi_meta2_sign;
   uint32_t mi_maxreaders;   /**< Total reader slots in the environment */
   uint32_t mi_numreaders;   /**< Max reader slots used in the environment */
   uint32_t mi_dxb_pagesize; /**< Database pagesize */
@@ -2590,7 +2643,7 @@ struct MDBX_envinfo {
   struct {
     struct {
       uint64_t x, y;
-    } current, meta0, meta1, meta2;
+    } current, meta[3];
   } mi_bootid;
 
   /** Bytes not explicitly synchronized to disk */
@@ -2891,6 +2944,83 @@ LIBMDBX_INLINE_API(int, mdbx_env_close, (MDBX_env * env)) {
   return mdbx_env_close_ex(env, false);
 }
 
+#if defined(DOXYGEN) || !(defined(_WIN32) || defined(_WIN64))
+/** \brief Восстанавливает экземпляр среды в дочернем процессе после ветвления
+ * родительского процесса посредством `fork()` и родственных системных вызовов.
+ * \ingroup c_extra
+ *
+ * Без вызова \ref mdbx_env_resurrect_after_fork() использование открытого
+ * экземпляра среды в дочернем процессе не возможно, включая все выполняющиеся
+ * на момент ветвления транзакции.
+ *
+ * Выполняемые функцией действия можно рассматривать как повторное открытие БД
+ * в дочернем процессе, с сохранением заданных опций и адресов уже созданных
+ * экземпляров объектов связанных с API.
+ *
+ * \note Функция не доступна в ОС семейства Windows по причине отсутствия
+ * функционала ветвления процесса в API операционной системы.
+ *
+ * Ветвление не оказывает влияния на состояние MDBX-среды в родительском
+ * процессе. Все транзакции, которые были в родительском процессе на момент
+ * ветвления, после ветвления в родительском процессе продолжат выполняться без
+ * помех. Но в дочернем процессе все соответствующие транзакции безальтернативно
+ * перестают быть валидными, а попытка их использования приведет к возврату
+ * ошибки или отправке `SIGSEGV`.
+ *
+ * Использование экземпляра среды в дочернем процессе не возможно до вызова
+ * \ref mdbx_env_resurrect_after_fork(), так как в результате ветвления у
+ * процесса меняется PID, значение которого используется для организации
+ * совместно работы с БД, в том числе, для отслеживания процессов/потоков
+ * выполняющих читающие транзакции связанные с соответствующими снимками данных.
+ * Все активные на момент ветвления транзакции не могут продолжаться в дочернем
+ * процессе, так как не владеют какими-либо блокировками или каким-либо снимком
+ * данных и не удерживает его от переработки при сборке мусора.
+ *
+ * Функция \ref mdbx_env_resurrect_after_fork() восстанавливает переданный
+ * экземпляр среды в дочернем процессе после ветвления, а именно: обновляет
+ * используемые системные идентификаторы, повторно открывает дескрипторы файлов,
+ * производит захват необходимых блокировок связанных с LCK- и DXB-файлами БД,
+ * восстанавливает отображения в память страницы БД, таблицы читателей и
+ * служебных/вспомогательных данных в память. Однако унаследованные от
+ * родительского процесса транзакции не восстанавливаются, прием пишущие и
+ * читающие транзакции обрабатываются по-разному:
+ *
+ *  - Пишущая транзакция, если таковая была на момент ветвления,
+ *    прерывается в дочернем процессе с освобождение связанных с ней ресурсов,
+ *    включая все вложенные транзакции.
+ *
+ *  - Читающие же транзакции, если таковые были в родительском процессе,
+ *    в дочернем процессе логически прерываются, но без освобождения ресурсов.
+ *    Поэтому необходимо обеспечить вызов \ref mdbx_txn_abort() для каждой
+ *    такой читающей транзакций в дочернем процессе, либо смириться с утечкой
+ *    ресурсов до завершения дочернего процесса.
+ *
+ * Причина не-освобождения ресурсов читающих транзакций в том, что исторически
+ * MDBX не ведет какой-либо общий список экземпляров читающих, так как это не
+ * требуется для штатных режимов работы, но требует использования атомарных
+ * операций или дополнительных объектов синхронизации при создании/разрушении
+ * экземпляров \ref MDBX_txn.
+ *
+ * Вызов \ref mdbx_env_resurrect_after_fork() без ветвления, не в дочернем
+ * процессе, либо повторные вызовы не приводят к каким-либо действиям или
+ * изменениям.
+ *
+ * \returns Ненулевое значение ошибки при сбое и 0 при успешном выполнении,
+ *          некоторые возможные ошибки таковы:
+ *
+ * \retval MDBX_BUSY      В родительском процессе БД была открыта
+ *                        в режиме \ref MDBX_EXCLUSIVE.
+ *
+ * \retval MDBX_EBADSIGN  При повреждении сигнатуры экземпляра объекта, а также
+ *                        в случае одновременного вызова \ref
+ *                        mdbx_env_resurrect_after_fork() из разных потоков.
+ *
+ * \retval MDBX_PANIC     Произошла критическая ошибка при восстановлении
+ *                        экземпляра среды, либо такая ошибка уже была
+ *                        до вызова функции. */
+LIBMDBX_API int mdbx_env_resurrect_after_fork(MDBX_env *env);
+#endif /* Windows */
+
 /** \brief Warming up options
  * \ingroup c_settings
  * \anchor warmup_flags
@@ -3310,6 +3440,12 @@ mdbx_limits_dbsize_max(intptr_t pagesize);
 MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API intptr_t
 mdbx_limits_keysize_max(intptr_t pagesize, MDBX_db_flags_t flags);
 
+/** \brief Returns minimal key size in bytes for given database flags.
+ * \ingroup c_statinfo
+ * \see db_flags */
+MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API intptr_t
+mdbx_limits_keysize_min(MDBX_db_flags_t flags);
+
 /** \brief Returns maximal data size in bytes for given page size
  * and database flags, or -1 if pagesize is invalid.
  * \ingroup c_statinfo
@@ -3317,6 +3453,12 @@ mdbx_limits_keysize_max(intptr_t pagesize, MDBX_db_flags_t flags);
 MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API intptr_t
 mdbx_limits_valsize_max(intptr_t pagesize, MDBX_db_flags_t flags);
 
+/** \brief Returns minimal data size in bytes for given database flags.
+ * \ingroup c_statinfo
+ * \see db_flags */
+MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API intptr_t
+mdbx_limits_valsize_min(MDBX_db_flags_t flags);
+
 /** \brief Returns maximal size of key-value pair to fit in a single page with
  * the given size and database flags, or -1 if pagesize is invalid.
  * \ingroup c_statinfo
@@ -3766,7 +3908,7 @@ mdbx_txn_env(const MDBX_txn *txn);
  * \param [in] txn  A transaction handle returned by \ref mdbx_txn_begin().
  *
  * \returns A transaction flags, valid if input is an valid transaction,
- *          otherwise -1. */
+ *          otherwise \ref MDBX_TXN_INVALID. */
 MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int mdbx_txn_flags(const MDBX_txn *txn);
 
 /** \brief Return the transaction's ID.
@@ -4221,6 +4363,11 @@ MDBX_DEPRECATED LIBMDBX_API int
 mdbx_dbi_open_ex2(MDBX_txn *txn, const MDBX_val *name, MDBX_db_flags_t flags,
                   MDBX_dbi *dbi, MDBX_cmp_func *keycmp, MDBX_cmp_func *datacmp);
 
+/** FIXME */
+LIBMDBX_API int mdbx_dbi_rename(MDBX_txn *txn, MDBX_dbi dbi, const char *name);
+LIBMDBX_API int mdbx_dbi_rename2(MDBX_txn *txn, MDBX_dbi dbi,
+                                 const MDBX_val *name);
+
 /** \defgroup value2key Value-to-Key functions
  * \brief Value-to-Key functions to
  * \ref avoid_custom_comparators "avoid using custom comparators"
@@ -4734,6 +4881,28 @@ mdbx_cursor_get_userctx(const MDBX_cursor *cursor);
 LIBMDBX_API int mdbx_cursor_bind(const MDBX_txn *txn, MDBX_cursor *cursor,
                                  MDBX_dbi dbi);
 
+/** \brief Unbind cursor from a transaction.
+ * \ingroup c_cursors
+ *
+ * Unbinded cursor is disassociated with any transactions but still holds
+ * the original DBI-handle internally. Thus it could be renewed with any running
+ * transaction or closed.
+ *
+ * \see mdbx_cursor_renew()
+ * \see mdbx_cursor_bind()
+ * \see mdbx_cursor_close()
+ *
+ * \note In contrast to LMDB, the MDBX required that any opened cursors can be
+ * reused and must be freed explicitly, regardless ones was opened in a
+ * read-only or write transaction. The REASON for this is eliminates ambiguity
+ * which helps to avoid errors such as: use-after-free, double-free, i.e.
+ * memory corruption and segfaults.
+ *
+ * \param [in] cursor   A cursor handle returned by \ref mdbx_cursor_open().
+ *
+ * \returns A non-zero error value on failure and 0 on success. */
+LIBMDBX_API int mdbx_cursor_unbind(MDBX_cursor *cursor);
+
 /** \brief Create a cursor handle for the specified transaction and DBI handle.
  * \ingroup c_cursors
  *
@@ -4783,6 +4952,27 @@ LIBMDBX_API int mdbx_cursor_open(const MDBX_txn *txn, MDBX_dbi dbi,
  *                     or \ref mdbx_cursor_create(). */
 LIBMDBX_API void mdbx_cursor_close(MDBX_cursor *cursor);
 
+/** \brief Unbind or closes all cursors of a given transaction.
+ * \ingroup c_cursors
+ *
+ * Unbinds either closes all cursors associated (opened or renewed) with
+ * a given transaction in a bulk with minimal overhead.
+ *
+ * \see mdbx_cursor_unbind()
+ * \see mdbx_cursor_close()
+ *
+ * \param [in] txn      A transaction handle returned by \ref mdbx_txn_begin().
+ * \param [in] unbind   If non-zero, unbinds cursors and leaves ones reusable.
+ *                      Otherwise close and dispose cursors.
+ *
+ * \returns A negative error value on failure or the number of closed cursors
+ *          on success, some possible errors are:
+ * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
+ *                               by current thread.
+ * \retval MDBX_BAD_TXN          Given transaction is invalid or has
+ *                               a child/nested transaction transaction. */
+LIBMDBX_API int mdbx_txn_release_all_cursors(const MDBX_txn *txn, bool unbind);
+
 /** \brief Renew a cursor handle for use within the given transaction.
  * \ingroup c_cursors
  *
@@ -4834,6 +5024,11 @@ LIBMDBX_API MDBX_dbi mdbx_cursor_dbi(const MDBX_cursor *cursor);
  * \returns A non-zero error value on failure and 0 on success. */
 LIBMDBX_API int mdbx_cursor_copy(const MDBX_cursor *src, MDBX_cursor *dest);
 
+/** FIXME */
+LIBMDBX_API int mdbx_cursor_compare(const MDBX_cursor *left,
+                                    const MDBX_cursor *right,
+                                    bool ignore_nested);
+
 /** \brief Retrieve by cursor.
  * \ingroup c_crud
  *
@@ -4867,6 +5062,21 @@ LIBMDBX_API int mdbx_cursor_copy(const MDBX_cursor *src, MDBX_cursor *dest);
  * \retval MDBX_EINVAL    An invalid parameter was specified. */
 LIBMDBX_API int mdbx_cursor_get(MDBX_cursor *cursor, MDBX_val *key,
                                 MDBX_val *data, MDBX_cursor_op op);
+/** FIXME */
+typedef int(MDBX_predicate_func)(void *context, MDBX_val *key, MDBX_val *value,
+                                 void *arg) MDBX_CXX17_NOEXCEPT;
+/** FIXME */
+LIBMDBX_API int mdbx_cursor_scan(MDBX_cursor *cursor,
+                                 MDBX_predicate_func *predicate, void *context,
+                                 MDBX_cursor_op start_op,
+                                 MDBX_cursor_op turn_op, void *arg);
+
+/** FIXME */
+LIBMDBX_API int mdbx_cursor_scan_from(MDBX_cursor *cursor,
+                                      MDBX_predicate_func *predicate,
+                                      void *context, MDBX_cursor_op from_op,
+                                      MDBX_val *from_key, MDBX_val *from_value,
+                                      MDBX_cursor_op turn_op, void *arg);
 
 /** \brief Retrieve multiple non-dupsort key/value pairs by cursor.
  * \ingroup c_crud
@@ -5076,6 +5286,10 @@ mdbx_cursor_eof(const MDBX_cursor *cursor);
 MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
 mdbx_cursor_on_first(const MDBX_cursor *cursor);
 
+/** FIXME */
+MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
+mdbx_cursor_on_first_dup(const MDBX_cursor *cursor);
+
 /** \brief Determines whether the cursor is pointed to the last key-value pair
  * or not.
  * \ingroup c_cursors
@@ -5090,6 +5304,10 @@ mdbx_cursor_on_first(const MDBX_cursor *cursor);
 MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
 mdbx_cursor_on_last(const MDBX_cursor *cursor);
 
+/** FIXME */
+MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
+mdbx_cursor_on_last_dup(const MDBX_cursor *cursor);
+
 /** \addtogroup c_rqest
  * \details \note The estimation result varies greatly depending on the filling
  * of specific pages and the overall balance of the b-tree:
@@ -5521,48 +5739,21 @@ LIBMDBX_API int mdbx_env_set_hsr(MDBX_env *env, MDBX_hsr_func *hsr_callback);
 MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API MDBX_hsr_func *
 mdbx_env_get_hsr(const MDBX_env *env);
 
-/** \defgroup btree_traversal B-tree Traversal
+/** \defgroup chk Checking and Recovery
- * This is internal API for mdbx_chk tool. You should avoid to use it, except
+ * Basically this is internal API for `mdbx_chk` tool, etc.
- * some extremal special cases.
+ * You should avoid to use it, except some extremal special cases.
  * \ingroup c_extra
  * @{ */
 
-/** \brief Page types for traverse the b-tree.
+/** \brief Acquires write-transaction lock.
- * \see mdbx_env_pgwalk() \see MDBX_pgvisitor_func */
+ * Provided for custom and/or complex locking scenarios.
-enum MDBX_page_type_t {
+ * \returns A non-zero error value on failure and 0 on success. */
-  MDBX_page_broken,
+LIBMDBX_API int mdbx_txn_lock(MDBX_env *env, bool dont_wait);
-  MDBX_page_meta,
-  MDBX_page_large,
-  MDBX_page_branch,
-  MDBX_page_leaf,
-  MDBX_page_dupfixed_leaf,
-  MDBX_subpage_leaf,
-  MDBX_subpage_dupfixed_leaf,
-  MDBX_subpage_broken,
-};
-#ifndef __cplusplus
-typedef enum MDBX_page_type_t MDBX_page_type_t;
-#endif
 
-/** \brief Pseudo-name for MainDB */
+/** \brief Releases write-transaction lock.
-#define MDBX_PGWALK_MAIN ((void *)((ptrdiff_t)0))
+ * Provided for custom and/or complex locking scenarios.
-/** \brief Pseudo-name for GarbageCollectorDB */
+ * \returns A non-zero error value on failure and 0 on success. */
-#define MDBX_PGWALK_GC ((void *)((ptrdiff_t)-1))
+LIBMDBX_API int mdbx_txn_unlock(MDBX_env *env);
-/** \brief Pseudo-name for MetaPages */
-#define MDBX_PGWALK_META ((void *)((ptrdiff_t)-2))
-
-/** \brief Callback function for traverse the b-tree. \see mdbx_env_pgwalk() */
-typedef int
-MDBX_pgvisitor_func(const uint64_t pgno, const unsigned number, void *const ctx,
-                    const int deep, const MDBX_val *dbi_name,
-                    const size_t page_size, const MDBX_page_type_t type,
-                    const MDBX_error_t err, const size_t nentries,
-                    const size_t payload_bytes, const size_t header_bytes,
-                    const size_t unused_bytes) MDBX_CXX17_NOEXCEPT;
-
-/** \brief B-tree traversal function. */
-LIBMDBX_API int mdbx_env_pgwalk(MDBX_txn *txn, MDBX_pgvisitor_func *visitor,
-                                void *ctx, bool dont_check_keys_ordering);
 
 /** \brief Open an environment instance using specific meta-page
  * for checking and recovery.
@@ -5594,7 +5785,236 @@ LIBMDBX_API int mdbx_env_open_for_recoveryW(MDBX_env *env,
  * leg(s). */
 LIBMDBX_API int mdbx_env_turn_for_recovery(MDBX_env *env, unsigned target_meta);
 
-/** end of btree_traversal @} */
+/** \brief FIXME
+ */
+LIBMDBX_API int mdbx_preopen_snapinfo(const char *pathname, MDBX_envinfo *arg,
+                                      size_t bytes);
+#if defined(_WIN32) || defined(_WIN64) || defined(DOXYGEN)
+/** \copydoc mdbx_preopen_snapinfo()
+ * \note Available only on Windows.
+ * \see mdbx_preopen_snapinfo() */
+LIBMDBX_API int mdbx_preopen_snapinfoW(const wchar_t *pathname,
+                                       MDBX_envinfo *arg, size_t bytes);
+#endif /* Windows */
+
+/** \brief Флаги/опции для проверки целостности БД.
+ * \see mdbx_env_chk() */
+enum MDBX_chk_flags_t {
+  /** Режим проверки по-умолчанию, в том числе в режиме только-чтения. */
+  MDBX_CHK_DEFAULTS = 0,
+
+  /** Проверка в режиме чтения-записи, с захватом блокировки и приостановки
+   * пишущих транзакций. */
+  MDBX_CHK_READWRITE = 1,
+
+  /** Пропустить обход дерева страниц. */
+  MDBX_CHK_SKIP_BTREE_TRAVERSAL = 2,
+
+  /** Пропустить просмотр записей ключ-значение. */
+  MDBX_CHK_SKIP_KV_TRAVERSAL = 4,
+
+  /** Игнорировать порядок ключей и записей.
+   * \note Требуется при проверке унаследованных БД созданных с использованием
+   * нестандартных (пользовательских) функций сравнения ключей или значений. */
+  MDBX_CHK_IGNORE_ORDER = 8
+};
+#ifndef __cplusplus
+/** \ingroup c_opening */
+typedef enum MDBX_chk_flags_t MDBX_chk_flags_t;
+#else
+DEFINE_ENUM_FLAG_OPERATORS(MDBX_chk_flags_t)
+#endif
+
+/** \brief Уровни логирование/детализации информации,
+ * поставляемой через обратные вызовы при проверке целостности БД.
+ * \see mdbx_env_chk() */
+enum MDBX_chk_severity {
+  MDBX_chk_severity_prio_shift = 4,
+  MDBX_chk_severity_kind_mask = 0xF,
+  MDBX_chk_fatal = 0x00u,
+  MDBX_chk_error = 0x11u,
+  MDBX_chk_warning = 0x22u,
+  MDBX_chk_notice = 0x33u,
+  MDBX_chk_result = 0x44u,
+  MDBX_chk_resolution = 0x55u,
+  MDBX_chk_processing = 0x56u,
+  MDBX_chk_info = 0x67u,
+  MDBX_chk_verbose = 0x78u,
+  MDBX_chk_details = 0x89u,
+  MDBX_chk_extra = 0x9Au
+};
+
+/** \brief Стадии проверки,
+ * сообщаемые через обратные вызовы при проверке целостности БД.
+ * \see mdbx_env_chk() */
+enum MDBX_chk_stage {
+  MDBX_chk_none,
+  MDBX_chk_init,
+  MDBX_chk_lock,
+  MDBX_chk_meta,
+  MDBX_chk_traversal_tree,
+  MDBX_chk_traversal_freedb,
+  MDBX_chk_space,
+  MDBX_chk_traversal_maindb,
+  MDBX_chk_traversal_subdbs,
+  MDBX_chk_conclude,
+  MDBX_chk_unlock,
+  MDBX_chk_finalize
+};
+
+/** \brief Виртуальная строка отчета, формируемого при проверке целостности БД.
+ * \see mdbx_env_chk() */
+typedef struct MDBX_chk_line {
+  struct MDBX_chk_context *ctx;
+  uint8_t severity, scope_depth, empty;
+  char *begin, *end, *out;
+} MDBX_chk_line_t;
+
+/** \brief Проблема обнаруженная при проверке целостности БД.
+ * \see mdbx_env_chk() */
+typedef struct MDBX_chk_issue {
+  struct MDBX_chk_issue *next;
+  size_t count;
+  const char *caption;
+} MDBX_chk_issue_t;
+
+/** \brief Иерархический контекст при проверке целостности БД.
+ * \see mdbx_env_chk() */
+typedef struct MDBX_chk_scope {
+  MDBX_chk_issue_t *issues;
+  struct MDBX_chk_internal *internal;
+  const void *object;
+  enum MDBX_chk_stage stage;
+  enum MDBX_chk_severity verbosity;
+  size_t subtotal_issues;
+  union {
+    void *ptr;
+    size_t number;
+  } usr_z, usr_v, usr_o;
+} MDBX_chk_scope_t;
+
+/** \brief Пользовательский тип для привязки дополнительных данных,
+ * связанных с некоторой таблицей ключ-значение, при проверке целостности БД.
+ * \see mdbx_env_chk() */
+typedef struct MDBX_chk_user_subdb_cookie MDBX_chk_user_subdb_cookie_t;
+
+/** \brief Гистограмма с некоторой статистической информацией,
+ * собираемой при проверке целостности БД.
+ * \see mdbx_env_chk() */
+struct MDBX_chk_histogram {
+  size_t amount, count, ones, pad;
+  struct {
+    size_t begin, end, amount, count;
+  } ranges[9];
+};
+
+/** \brief Информация о некоторой таблицей ключ-значение,
+ * при проверке целостности БД.
+ * \see mdbx_env_chk() */
+typedef struct MDBX_chk_subdb {
+  MDBX_chk_user_subdb_cookie_t *cookie;
+
+/** \brief Pseudo-name for MainDB */
+#define MDBX_CHK_MAIN ((void *)((ptrdiff_t)0))
+/** \brief Pseudo-name for GarbageCollectorDB */
+#define MDBX_CHK_GC ((void *)((ptrdiff_t)-1))
+/** \brief Pseudo-name for MetaPages */
+#define MDBX_CHK_META ((void *)((ptrdiff_t)-2))
+
+  MDBX_val name;
+  MDBX_db_flags_t flags;
+  int id;
+
+  size_t payload_bytes, lost_bytes;
+  struct {
+    size_t all, empty, other;
+    size_t branch, leaf;
+    size_t nested_branch, nested_leaf, nested_subleaf;
+  } pages;
+  struct {
+    /// Tree deep histogram
+    struct MDBX_chk_histogram deep;
+    /// Histogram of large/overflow pages length
+    struct MDBX_chk_histogram large_pages;
+    /// Histogram of nested trees height, span length for GC
+    struct MDBX_chk_histogram nested_tree;
+    /// Keys length histogram
+    struct MDBX_chk_histogram key_len;
+    /// Values length histogram
+    struct MDBX_chk_histogram val_len;
+  } histogram;
+} MDBX_chk_subdb_t;
+
+/** \brief Контекст проверки целостности БД.
+ * \see mdbx_env_chk() */
+typedef struct MDBX_chk_context {
+  struct MDBX_chk_internal *internal;
+  MDBX_env *env;
+  MDBX_txn *txn;
+  MDBX_chk_scope_t *scope;
+  uint8_t scope_nesting;
+  struct {
+    size_t total_payload_bytes;
+    size_t subdb_total, subdb_processed;
+    size_t total_unused_bytes, unused_pages;
+    size_t processed_pages, reclaimable_pages, gc_pages, alloc_pages,
+        backed_pages;
+    size_t problems_meta, tree_problems, gc_tree_problems, kv_tree_problems,
+        problems_gc, problems_kv, total_problems;
+    uint64_t steady_txnid, recent_txnid;
+    /** Указатель на массив размером subdb_total с указателями на экземпляры
+     * структур MDBX_chk_subdb_t с информацией о всех таблицах ключ-значение,
+     * включая MainDB и GC/FreeDB. */
+    const MDBX_chk_subdb_t *const *subdbs;
+  } result;
+} MDBX_chk_context_t;
+
+/** FIXME */
+typedef struct MDBX_chk_callbacks {
+  bool (*check_break)(MDBX_chk_context_t *ctx);
+  int (*scope_push)(MDBX_chk_context_t *ctx, MDBX_chk_scope_t *outer,
+                    MDBX_chk_scope_t *inner, const char *fmt, va_list args);
+  int (*scope_conclude)(MDBX_chk_context_t *ctx, MDBX_chk_scope_t *outer,
+                        MDBX_chk_scope_t *inner, int err);
+  void (*scope_pop)(MDBX_chk_context_t *ctx, MDBX_chk_scope_t *outer,
+                    MDBX_chk_scope_t *inner);
+  void (*issue)(MDBX_chk_context_t *ctx, const char *object,
+                uint64_t entry_number, const char *issue, const char *extra_fmt,
+                va_list extra_args);
+  MDBX_chk_user_subdb_cookie_t *(*subdb_filter)(MDBX_chk_context_t *ctx,
+                                                const MDBX_val *name,
+                                                MDBX_db_flags_t flags);
+  int (*subdb_conclude)(MDBX_chk_context_t *ctx, const MDBX_chk_subdb_t *subdb,
+                        MDBX_cursor *cursor, int err);
+  void (*subdb_dispose)(MDBX_chk_context_t *ctx, const MDBX_chk_subdb_t *subdb);
+
+  int (*subdb_handle_kv)(MDBX_chk_context_t *ctx, const MDBX_chk_subdb_t *subdb,
+                         size_t entry_number, const MDBX_val *key,
+                         const MDBX_val *value);
+
+  int (*stage_begin)(MDBX_chk_context_t *ctx, enum MDBX_chk_stage);
+  int (*stage_end)(MDBX_chk_context_t *ctx, enum MDBX_chk_stage, int err);
+
+  MDBX_chk_line_t *(*print_begin)(MDBX_chk_context_t *ctx,
+                                  enum MDBX_chk_severity severity);
+  void (*print_flush)(MDBX_chk_line_t *);
+  void (*print_done)(MDBX_chk_line_t *);
+  void (*print_chars)(MDBX_chk_line_t *, const char *str, size_t len);
+  void (*print_format)(MDBX_chk_line_t *, const char *fmt, va_list args);
+  void (*print_size)(MDBX_chk_line_t *, const char *prefix,
+                     const uint64_t value, const char *suffix);
+} MDBX_chk_callbacks_t;
+
+/** FIXME */
+LIBMDBX_API int mdbx_env_chk(MDBX_env *env, const MDBX_chk_callbacks_t *cb,
+                             MDBX_chk_context_t *ctx,
+                             const enum MDBX_chk_flags_t flags,
+                             enum MDBX_chk_severity verbosity,
+                             unsigned timeout_seconds_16dot16);
+/** FIXME */
+LIBMDBX_API int mdbx_env_chk_problem(MDBX_chk_context_t *ctx);
+
+/** end of chk @} */
 
 /** end of c_api @} */
 

src/base.h

@@ -48,6 +48,7 @@
 #include <stdlib.h>
 
 #include <assert.h>
+#include <ctype.h>
 #include <fcntl.h>
 #include <limits.h>
 #include <stdio.h>
@@ -685,7 +686,7 @@ __extern_C key_t ftok(const char *, int);
 
 /*----------------------------------------------------------------------------*/
 
-#if defined(MDBX_USE_VALGRIND)
+#if defined(ENABLE_MEMCHECK)
 #include <valgrind/memcheck.h>
 #ifndef VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE
 /* LY: available since Valgrind 3.10 */
@@ -707,7 +708,7 @@ __extern_C key_t ftok(const char *, int);
 #define VALGRIND_CHECK_MEM_IS_ADDRESSABLE(a, s) (0)
 #define VALGRIND_CHECK_MEM_IS_DEFINED(a, s) (0)
 #define RUNNING_ON_VALGRIND (0)
-#endif /* MDBX_USE_VALGRIND */
+#endif /* ENABLE_MEMCHECK */
 
 #ifdef __SANITIZE_ADDRESS__
 #include <sanitizer/asan_interface.h>

src/bits.md

@@ -5,9 +5,9 @@ N |   MASK  | ENV       | TXN          | DB       | PUT       | DBI        | NOD
 2 |0000 0004|ALLOC_COLSC|TXN_DIRTY     |DUPSORT   |           |DBI_FRESH   |F_DUPDATA|P_OVERFLOW|         |
 3 |0000 0008|ALLOC_SSCAN|TXN_SPILLS    |INTEGERKEY|           |DBI_CREAT   |         |P_META    |         |
 4 |0000 0010|ALLOC_FIFO |TXN_HAS_CHILD |DUPFIXED  |NOOVERWRITE|DBI_VALID   |         |P_BAD     |         |
-5 |0000 0020|           |TXN_DRAINED_GC|INTEGERDUP|NODUPDATA  |DBI_USRVALID|         |P_LEAF2   |         |
+5 |0000 0020|           |TXN_DRAINED_GC|INTEGERDUP|NODUPDATA  |            |         |P_LEAF2   |         |
-6 |0000 0040|           |              |REVERSEDUP|CURRENT    |DBI_DUPDATA |         |P_SUBP    |         |
+6 |0000 0040|           |              |REVERSEDUP|CURRENT    |DBI_OLDEN   |         |P_SUBP    |         |
-7 |0000 0080|           |              |          |ALLDUPS    |DBI_AUDITED |         |          |         |
+7 |0000 0080|           |              |          |ALLDUPS    |DBI_LINDO   |         |          |         |
 8 |0000 0100| _MAY_MOVE |              |          |           |            |         |          | <=      |
 9 |0000 0200| _MAY_UNMAP|              |          |           |            |         |          | <=      |
 10|0000 0400|           |              |          |           |            |         |          |         |

src/config.h.in

@@ -5,7 +5,7 @@
 /* clang-format off */
 
 #cmakedefine LTO_ENABLED
-#cmakedefine MDBX_USE_VALGRIND
+#cmakedefine ENABLE_MEMCHECK
 #cmakedefine ENABLE_GPROF
 #cmakedefine ENABLE_GCOV
 #cmakedefine ENABLE_ASAN
@@ -33,6 +33,8 @@
 #cmakedefine01 MDBX_ENABLE_BIGFOOT
 #cmakedefine01 MDBX_ENABLE_PGOP_STAT
 #cmakedefine01 MDBX_ENABLE_PROFGC
+#cmakedefine01 MDBX_ENABLE_DBI_SPARSE
+#cmakedefine01 MDBX_ENABLE_DBI_LOCKFREE
 
 /* Windows */
 #cmakedefine01 MDBX_WITHOUT_MSVC_CRT

src/internals.h

@@ -93,6 +93,10 @@
         disable : 5105) /* winbase.h(9531): warning C5105: macro expansion     \
                            producing 'defined' has undefined behavior */
 #endif
+#if _MSC_VER < 1920
+/* avoid "error C2219: syntax error: type qualifier must be after '*'" */
+#define __restrict
+#endif
 #if _MSC_VER > 1930
 #pragma warning(disable : 6235) /* <expression> is always a constant */
 #pragma warning(disable : 6237) /* <expression> is never evaluated and might   \
@@ -703,7 +707,8 @@ typedef struct MDBX_page {
 
 #define PAGETYPE_WHOLE(p) ((uint8_t)(p)->mp_flags)
 
-/* Drop legacy P_DIRTY flag for sub-pages for compatilibity */
+/* Drop legacy P_DIRTY flag for sub-pages for compatilibity,
+ * for assertions only. */
 #define PAGETYPE_COMPAT(p)                                                     \
   (unlikely(PAGETYPE_WHOLE(p) & P_SUBP)                                        \
        ? PAGETYPE_WHOLE(p) & ~(P_SUBP | P_LEGACY_DIRTY)                        \
@@ -812,7 +817,7 @@ typedef sem_t osal_ipclock_t;
 #endif /* MDBX_LOCKING */
 
 #if MDBX_LOCKING > MDBX_LOCKING_SYSV && !defined(__cplusplus)
-MDBX_INTERNAL_FUNC int osal_ipclock_stub(osal_ipclock_t *ipc);
+MDBX_INTERNAL_FUNC int osal_ipclock_stubinit(osal_ipclock_t *ipc);
 MDBX_INTERNAL_FUNC int osal_ipclock_destroy(osal_ipclock_t *ipc);
 #endif /* MDBX_LOCKING */
 
@@ -1136,10 +1141,10 @@ typedef struct troika {
 #if MDBX_WORDBITS > 32 /* Workaround for false-positives from Valgrind */
   uint32_t unused_pad;
 #endif
-#define TROIKA_HAVE_STEADY(troika) ((troika)->fsm & 7)
+#define TROIKA_HAVE_STEADY(troika) ((troika)->fsm & 7u)
-#define TROIKA_STRICT_VALID(troika) ((troika)->tail_and_flags & 64)
+#define TROIKA_STRICT_VALID(troika) ((troika)->tail_and_flags & 64u)
-#define TROIKA_VALID(troika) ((troika)->tail_and_flags & 128)
+#define TROIKA_VALID(troika) ((troika)->tail_and_flags & 128u)
-#define TROIKA_TAIL(troika) ((troika)->tail_and_flags & 3)
+#define TROIKA_TAIL(troika) ((troika)->tail_and_flags & 3u)
   txnid_t txnid[NUM_METAS];
 } meta_troika_t;
 
@@ -1169,6 +1174,8 @@ struct MDBX_txn {
 #error "Oops, some txn flags overlapped or wrong"
 #endif
   uint32_t mt_flags;
+  unsigned mt_numdbs;
+  size_t mt_owner; /* thread ID that owns this transaction */
 
   MDBX_txn *mt_parent; /* parent of a nested txn */
   /* Nested txn under this txn, set together with flag MDBX_TXN_HAS_CHILD */
@@ -1186,31 +1193,30 @@ struct MDBX_txn {
   txnid_t mt_front;
 
   MDBX_env *mt_env; /* the DB environment */
-  /* Array of records for each DB known in the environment. */
-  MDBX_dbx *mt_dbxs;
   /* Array of MDBX_db records for each known DB */
   MDBX_db *mt_dbs;
-  /* Array of sequence numbers for each DB handle */
-  MDBX_atomic_uint32_t *mt_dbiseqs;
 
-  /* Transaction DBI Flags */
+#if MDBX_ENABLE_DBI_SPARSE
-#define DBI_DIRTY MDBX_DBI_DIRTY /* DB was written in this txn */
+  unsigned *__restrict mt_dbi_sparse;
-#define DBI_STALE MDBX_DBI_STALE /* Named-DB record is older than txnID */
+#endif /* MDBX_ENABLE_DBI_SPARSE */
-#define DBI_FRESH MDBX_DBI_FRESH /* Named-DB handle opened in this txn */
+
-#define DBI_CREAT MDBX_DBI_CREAT /* Named-DB handle created in this txn */
+  /* Non-shared DBI state flags inside transaction */
-#define DBI_VALID 0x10           /* DB handle is valid, see also DB_VALID */
+#define DBI_DIRTY 0x01 /* DB was written in this txn */
-#define DBI_USRVALID 0x20        /* As DB_VALID, but not set for FREE_DBI */
+#define DBI_STALE 0x02 /* Named-DB record is older than txnID */
-#define DBI_AUDITED 0x40         /* Internal flag for accounting during audit */
+#define DBI_FRESH 0x04 /* Named-DB handle opened in this txn */
-  /* Array of flags for each DB */
+#define DBI_CREAT 0x08 /* Named-DB handle created in this txn */
-  uint8_t *mt_dbistate;
+#define DBI_VALID 0x10 /* Handle is valid, see also DB_VALID */
-  /* Number of DB records in use, or 0 when the txn is finished.
+#define DBI_OLDEN 0x40 /* Handle was closed/reopened outside txn */
-   * This number only ever increments until the txn finishes; we
+#define DBI_LINDO 0x80 /* Lazy initialization done for DBI-slot */
-   * don't decrement it when individual DB handles are closed. */
+  /* Array of non-shared txn's flags of DBI */
-  MDBX_dbi mt_numdbs;
+  uint8_t *__restrict mt_dbi_state;
-  size_t mt_owner; /* thread ID that owns this transaction */
+
+  /* Array of sequence numbers for each DB handle. */
+  uint32_t *__restrict mt_dbi_seqs;
+  MDBX_cursor **mt_cursors;
+
   MDBX_canary mt_canary;
   void *mt_userctx; /* User-settable context */
-  MDBX_cursor **mt_cursors;
 
   union {
     struct {
@@ -1220,8 +1226,8 @@ struct MDBX_txn {
     struct {
       meta_troika_t troika;
       /* In write txns, array of cursors for each DB */
-      MDBX_PNL relist;        /* Reclaimed GC pages */
+      MDBX_PNL __restrict relist; /* Reclaimed GC pages */
-      txnid_t last_reclaimed; /* ID of last used record */
+      txnid_t last_reclaimed;     /* ID of last used record */
 #if MDBX_ENABLE_REFUND
       pgno_t loose_refund_wl /* FIXME: describe */;
 #endif /* MDBX_ENABLE_REFUND */
@@ -1233,14 +1239,14 @@ struct MDBX_txn {
        * dirtylist into mt_parent after freeing hidden mt_parent pages. */
       size_t dirtyroom;
       /* For write txns: Modified pages. Sorted when not MDBX_WRITEMAP. */
-      MDBX_dpl *dirtylist;
+      MDBX_dpl *__restrict dirtylist;
       /* The list of reclaimed txns from GC */
-      MDBX_TXL lifo_reclaimed;
+      MDBX_TXL __restrict lifo_reclaimed;
       /* The list of pages that became unused during this transaction. */
-      MDBX_PNL retired_pages;
+      MDBX_PNL __restrict retired_pages;
       /* The list of loose pages that became unused and may be reused
        * in this transaction, linked through `mp_next`. */
-      MDBX_page *loose_pages;
+      MDBX_page *__restrict loose_pages;
       /* Number of loose pages (tw.loose_pages) */
       size_t loose_count;
       union {
@@ -1249,11 +1255,12 @@ struct MDBX_txn {
           /* The sorted list of dirty pages we temporarily wrote to disk
            * because the dirty list was full. page numbers in here are
            * shifted left by 1, deleted slots have the LSB set. */
-          MDBX_PNL list;
+          MDBX_PNL __restrict list;
         } spilled;
         size_t writemap_dirty_npages;
         size_t writemap_spilled_npages;
       };
+      uint64_t gc_time_acc;
     } tw;
   };
 };
@@ -1292,8 +1299,8 @@ struct MDBX_cursor {
   MDBX_db *mc_db;
   /* The database auxiliary record for this cursor */
   MDBX_dbx *mc_dbx;
-  /* The mt_dbistate for this database */
+  /* The mt_dbi_state[] for this DBI */
-  uint8_t *mc_dbistate;
+  uint8_t *__restrict mc_dbi_state;
   uint8_t mc_snum; /* number of pushed pages */
   uint8_t mc_top;  /* index of top page, normally mc_snum-1 */
 
@@ -1346,6 +1353,11 @@ typedef struct MDBX_cursor_couple {
   MDBX_xcursor inner;
 } MDBX_cursor_couple;
 
+struct mdbx_defer_free_item {
+  struct mdbx_defer_free_item *next;
+  uint64_t timestamp;
+};
+
 /* The database environment. */
 struct MDBX_env {
   /* ----------------------------------------------------- mostly static part */
@@ -1363,6 +1375,7 @@ struct MDBX_env {
 #define MDBX_DEPRECATED_COALESCE UINT32_C(0x2000000)
 #define ENV_INTERNAL_FLAGS (MDBX_FATAL_ERROR | MDBX_ENV_ACTIVE | MDBX_ENV_TXKEY)
   uint32_t me_flags;
+  unsigned me_psize;       /* DB page size, initialized from me_os_psize */
   osal_mmap_t me_dxb_mmap; /* The main data file */
 #define me_map me_dxb_mmap.base
 #define me_lazy_fd me_dxb_mmap.fd
@@ -1375,7 +1388,6 @@ struct MDBX_env {
 #define me_lfd me_lck_mmap.fd
   struct MDBX_lockinfo *me_lck;
 
-  unsigned me_psize;          /* DB page size, initialized from me_os_psize */
   uint16_t me_leaf_nodemax;   /* max size of a leaf-node */
   uint16_t me_branch_nodemax; /* max size of a branch-node */
   uint16_t me_subpage_limit;
@@ -1393,13 +1405,15 @@ struct MDBX_env {
   MDBX_dbi me_maxdbs;         /* size of the DB table */
   uint32_t me_pid;            /* process ID of this env */
   osal_thread_key_t me_txkey; /* thread-key for readers */
-  pathchar_t *me_pathname;    /* path to the DB files */
+  struct {                    /* path to the DB files */
-  void *me_pbuf;              /* scratch area for DUPSORT put() */
+    pathchar_t *lck, *dxb, *specified;
-  MDBX_txn *me_txn0;          /* preallocated write transaction */
+    void *buffer;
-
+  } me_pathname;
-  MDBX_dbx *me_dbxs;                /* array of static DB info */
+  void *me_pbuf;                     /* scratch area for DUPSORT put() */
-  uint16_t *me_dbflags;             /* array of flags from MDBX_db.md_flags */
+  MDBX_txn *me_txn0;                 /* preallocated write transaction */
-  MDBX_atomic_uint32_t *me_dbiseqs; /* array of dbi sequence numbers */
+  MDBX_dbx *me_dbxs;                 /* array of static DB info */
+  uint16_t *__restrict me_db_flags;  /* array of flags from MDBX_db.md_flags */
+  MDBX_atomic_uint32_t *me_dbi_seqs; /* array of dbi sequence numbers */
   unsigned
       me_maxgc_ov1page; /* Number of pgno_t fit in a single overflow page */
   unsigned me_maxgc_per_branch;
@@ -1413,6 +1427,7 @@ struct MDBX_env {
     unsigned rp_augment_limit;
     unsigned dp_limit;
     unsigned dp_initial;
+    uint64_t gc_time_limit;
     uint8_t dp_loose_limit;
     uint8_t spill_max_denominator;
     uint8_t spill_min_denominator;
@@ -1422,6 +1437,8 @@ struct MDBX_env {
     unsigned writethrough_threshold;
 #endif /* Windows */
     bool prefault_write;
+    bool prefer_waf_insteadof_balance; /* Strive to minimize WAF instead of
+                                          balancing pages fullment */
     union {
       unsigned all;
       /* tracks options with non-auto values but tuned by user */
@@ -1451,20 +1468,23 @@ struct MDBX_env {
   } me_sysv_ipc;
 #endif /* MDBX_LOCKING == MDBX_LOCKING_SYSV */
   bool me_incore;
+  bool me_prefault_write;
 
-  MDBX_env *me_lcklist_next;
+#if MDBX_ENABLE_DBI_LOCKFREE
+  struct mdbx_defer_free_item *me_defer_free;
+#endif /* MDBX_ENABLE_DBI_LOCKFREE */
 
   /* --------------------------------------------------- mostly volatile part */
 
   MDBX_txn *me_txn; /* current write transaction */
   osal_fastmutex_t me_dbi_lock;
-  MDBX_dbi me_numdbs; /* number of DBs opened */
+  unsigned me_numdbs; /* number of DBs opened */
-  bool me_prefault_write;
 
-  MDBX_page *me_dp_reserve; /* list of malloc'ed blocks for re-use */
   unsigned me_dp_reserve_len;
+  MDBX_page *__restrict me_dp_reserve; /* list of malloc'ed blocks for re-use */
+
   /* PNL of pages that became unused in a write txn */
-  MDBX_PNL me_retired_pages;
+  MDBX_PNL __restrict me_retired_pages;
   osal_ioring_t me_ioring;
 
 #if defined(_WIN32) || defined(_WIN64)
@@ -1482,13 +1502,12 @@ struct MDBX_env {
 #if MDBX_DEBUG
   MDBX_assert_func *me_assert_func; /*  Callback for assertion failures */
 #endif
-#ifdef MDBX_USE_VALGRIND
+#ifdef ENABLE_MEMCHECK
   int me_valgrind_handle;
 #endif
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
+#if defined(ENABLE_MEMCHECK) || defined(__SANITIZE_ADDRESS__)
-  MDBX_atomic_uint32_t me_ignore_EDEADLK;
   pgno_t me_poison_edge;
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
+#endif /* ENABLE_MEMCHECK || __SANITIZE_ADDRESS__ */
 
 #ifndef xMDBX_DEBUG_SPILLING
 #define xMDBX_DEBUG_SPILLING 0
@@ -1548,10 +1567,6 @@ osal_flush_incoherent_mmap(const void *addr, size_t nbytes,
 
 MDBX_INTERNAL_FUNC int cleanup_dead_readers(MDBX_env *env, int rlocked,
                                             int *dead);
-MDBX_INTERNAL_FUNC int rthc_alloc(osal_thread_key_t *key, MDBX_reader *begin,
-                                  MDBX_reader *end);
-MDBX_INTERNAL_FUNC void rthc_remove(const osal_thread_key_t key);
-
 MDBX_INTERNAL_FUNC void global_ctor(void);
 MDBX_INTERNAL_FUNC void osal_ctor(void);
 MDBX_INTERNAL_FUNC void global_dtor(void);
@@ -1666,7 +1681,8 @@ typedef struct MDBX_node {
 /* mdbx_dbi_open() flags */
 #define DB_USABLE_FLAGS (DB_PERSISTENT_FLAGS | MDBX_CREATE | MDBX_DB_ACCEDE)
 
-#define DB_VALID 0x8000 /* DB handle is valid, for me_dbflags */
+#define DB_VALID 0x8000u  /* DB handle is valid, for me_db_flags */
+#define DB_POISON 0x7fffu /* update pending */
 #define DB_INTERNAL_FLAGS DB_VALID
 
 #if DB_INTERNAL_FLAGS & DB_USABLE_FLAGS
@@ -1792,3 +1808,33 @@ MDBX_MAYBE_UNUSED static void static_checks(void) {
           (size_t)(size), __LINE__);                                           \
     ASAN_UNPOISON_MEMORY_REGION(addr, size);                                   \
   } while (0)
+
+/******************************************************************************/
+
+/** \brief Page types for traverse the b-tree.
+ * \see mdbx_env_pgwalk() \see MDBX_pgvisitor_func */
+enum MDBX_page_type_t {
+  MDBX_page_broken,
+  MDBX_page_large,
+  MDBX_page_branch,
+  MDBX_page_leaf,
+  MDBX_page_dupfixed_leaf,
+  MDBX_subpage_leaf,
+  MDBX_subpage_dupfixed_leaf,
+  MDBX_subpage_broken,
+};
+typedef enum MDBX_page_type_t MDBX_page_type_t;
+
+typedef struct MDBX_walk_sdb {
+  MDBX_val name;
+  struct MDBX_db *internal, *nested;
+} MDBX_walk_sdb_t;
+
+/** \brief Callback function for traverse the b-tree. \see mdbx_env_pgwalk() */
+typedef int
+MDBX_pgvisitor_func(const size_t pgno, const unsigned number, void *const ctx,
+                    const int deep, const MDBX_walk_sdb_t *subdb,
+                    const size_t page_size, const MDBX_page_type_t page_type,
+                    const MDBX_error_t err, const size_t nentries,
+                    const size_t payload_bytes, const size_t header_bytes,
+                    const size_t unused_bytes);

src/lck-posix.c

@@ -120,7 +120,7 @@ mdbx_global_destructor(void) {
  *  - Блокировка таблицы читателей для регистрации,
  *    т.е. функции osal_rdt_lock() и osal_rdt_unlock().
  *  - Блокировка БД для пишущих транзакций,
- *    т.е. функции mdbx_txn_lock() и mdbx_txn_unlock().
+ *    т.е. функции osal_txn_lock() и osal_txn_unlock().
  *
  * Остальной функционал реализуется отдельно посредством файловых блокировок:
  *  - Первоначальный захват БД в режиме exclusive/shared и последующий перевод
@@ -294,7 +294,7 @@ MDBX_INTERNAL_FUNC int osal_rpid_check(MDBX_env *env, uint32_t pid) {
 /*---------------------------------------------------------------------------*/
 
 #if MDBX_LOCKING > MDBX_LOCKING_SYSV
-MDBX_INTERNAL_FUNC int osal_ipclock_stub(osal_ipclock_t *ipc) {
+MDBX_INTERNAL_FUNC int osal_ipclock_stubinit(osal_ipclock_t *ipc) {
 #if MDBX_LOCKING == MDBX_LOCKING_POSIX1988
   return sem_init(ipc, false, 1) ? errno : 0;
 #elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                \
@@ -527,15 +527,42 @@ MDBX_INTERNAL_FUNC int osal_lck_downgrade(MDBX_env *env) {
   return rc;
 }
 
-__cold MDBX_INTERNAL_FUNC int osal_lck_destroy(MDBX_env *env,
+MDBX_INTERNAL_FUNC int osal_lck_upgrade(MDBX_env *env, bool dont_wait) {
-                                               MDBX_env *inprocess_neighbor) {
+  assert(env->me_lfd != INVALID_HANDLE_VALUE);
   if (unlikely(osal_getpid() != env->me_pid))
     return MDBX_PANIC;
 
+  const int cmd = dont_wait ? op_setlk : op_setlkw;
+  int rc = lck_op(env->me_lfd, cmd, F_WRLCK, 0, 1);
+  if (rc == MDBX_SUCCESS && (env->me_flags & MDBX_EXCLUSIVE) == 0) {
+    rc = (env->me_pid > 1)
+             ? lck_op(env->me_lazy_fd, cmd, F_WRLCK, 0, env->me_pid - 1)
+             : MDBX_SUCCESS;
+    if (rc == MDBX_SUCCESS) {
+      rc = lck_op(env->me_lazy_fd, cmd, F_WRLCK, env->me_pid + 1,
+                  OFF_T_MAX - env->me_pid - 1);
+      if (rc != MDBX_SUCCESS && env->me_pid > 1 &&
+          lck_op(env->me_lazy_fd, op_setlk, F_UNLCK, 0, env->me_pid - 1))
+        rc = MDBX_PANIC;
+    }
+    if (rc != MDBX_SUCCESS && lck_op(env->me_lfd, op_setlk, F_RDLCK, 0, 1))
+      rc = MDBX_PANIC;
+  }
+  if (unlikely(rc != 0)) {
+    ERROR("%s, err %u", "lck", rc);
+    assert(MDBX_IS_ERROR(rc));
+  }
+  return rc;
+}
+
+__cold MDBX_INTERNAL_FUNC int osal_lck_destroy(MDBX_env *env,
+                                               MDBX_env *inprocess_neighbor,
+                                               const uint32_t current_pid) {
+  eASSERT(env, osal_getpid() == current_pid);
   int rc = MDBX_SUCCESS;
   struct stat lck_info;
-  MDBX_lockinfo *lck = env->me_lck_mmap.lck;
+  MDBX_lockinfo *lck = env->me_lck;
-  if (env->me_lfd != INVALID_HANDLE_VALUE && !inprocess_neighbor && lck &&
+  if (lck && lck == env->me_lck_mmap.lck && !inprocess_neighbor &&
       /* try get exclusive access */
       lck_op(env->me_lfd, op_setlk, F_WRLCK, 0, OFF_T_MAX) == 0 &&
       /* if LCK was not removed */
@@ -544,7 +571,8 @@ __cold MDBX_INTERNAL_FUNC int osal_lck_destroy(MDBX_env *env,
              (env->me_flags & MDBX_RDONLY) ? F_RDLCK : F_WRLCK, 0,
              OFF_T_MAX) == 0) {
 
-    VERBOSE("%p got exclusive, drown locks", (void *)env);
+    VERBOSE("%p got exclusive, drown ipc-locks", (void *)env);
+    eASSERT(env, current_pid == env->me_pid);
 #if MDBX_LOCKING == MDBX_LOCKING_SYSV
     if (env->me_sysv_ipc.semid != -1)
       rc = semctl(env->me_sysv_ipc.semid, 2, IPC_RMID) ? errno : 0;
@@ -558,13 +586,20 @@ __cold MDBX_INTERNAL_FUNC int osal_lck_destroy(MDBX_env *env,
     if (rc == 0) {
       const bool synced = lck->mti_unsynced_pages.weak == 0;
       osal_munmap(&env->me_lck_mmap);
-      if (synced)
+      if (synced && env->me_lfd != INVALID_HANDLE_VALUE)
         rc = ftruncate(env->me_lfd, 0) ? errno : 0;
     }
 
     jitter4testing(false);
   }
 
+  if (current_pid != env->me_pid) {
+    eASSERT(env, !inprocess_neighbor);
+    NOTICE("drown env %p after-fork pid %d -> %d",
+           __Wpedantic_format_voidptr(env), env->me_pid, current_pid);
+    inprocess_neighbor = nullptr;
+  }
+
   /* 1) POSIX's fcntl() locks (i.e. when op_setlk == F_SETLK) should be restored
    * after file was closed.
    *
@@ -761,7 +796,7 @@ bailout:
 #endif /* MDBX_LOCKING > 0 */
 }
 
-__cold static int mdbx_ipclock_failed(MDBX_env *env, osal_ipclock_t *ipc,
+__cold static int osal_ipclock_failed(MDBX_env *env, osal_ipclock_t *ipc,
                                       const int err) {
   int rc = err;
 #if MDBX_LOCKING == MDBX_LOCKING_POSIX2008 || MDBX_LOCKING == MDBX_LOCKING_SYSV
@@ -822,11 +857,6 @@ __cold static int mdbx_ipclock_failed(MDBX_env *env, osal_ipclock_t *ipc,
 #error "FIXME"
 #endif /* MDBX_LOCKING */
 
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-  if (rc == EDEADLK && atomic_load32(&env->me_ignore_EDEADLK, mo_Relaxed) > 0)
-    return rc;
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
-
   ERROR("mutex (un)lock failed, %s", mdbx_strerror(err));
   if (rc != EDEADLK)
     env->me_flags |= MDBX_FATAL_ERROR;
@@ -852,7 +882,7 @@ MDBX_INTERNAL_FUNC int osal_check_tid4bionic(void) {
 }
 #endif /* __ANDROID_API__ || ANDROID) || BIONIC */
 
-static int mdbx_ipclock_lock(MDBX_env *env, osal_ipclock_t *ipc,
+static int osal_ipclock_lock(MDBX_env *env, osal_ipclock_t *ipc,
                              const bool dont_wait) {
 #if MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                  \
     MDBX_LOCKING == MDBX_LOCKING_POSIX2008
@@ -888,63 +918,87 @@ static int mdbx_ipclock_lock(MDBX_env *env, osal_ipclock_t *ipc,
 #endif /* MDBX_LOCKING */
 
   if (unlikely(rc != MDBX_SUCCESS && rc != MDBX_BUSY))
-    rc = mdbx_ipclock_failed(env, ipc, rc);
+    rc = osal_ipclock_failed(env, ipc, rc);
   return rc;
 }
 
-static int mdbx_ipclock_unlock(MDBX_env *env, osal_ipclock_t *ipc) {
+int osal_ipclock_unlock(MDBX_env *env, osal_ipclock_t *ipc) {
+  int err = MDBX_ENOSYS;
 #if MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                  \
     MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-  int rc = pthread_mutex_unlock(ipc);
+  err = pthread_mutex_unlock(ipc);
-  (void)env;
 #elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-  int rc = sem_post(ipc) ? errno : MDBX_SUCCESS;
+  err = sem_post(ipc) ? errno : MDBX_SUCCESS;
-  (void)env;
 #elif MDBX_LOCKING == MDBX_LOCKING_SYSV
   if (unlikely(*ipc != (pid_t)env->me_pid))
-    return EPERM;
+    err = EPERM;
-  *ipc = 0;
+  else {
-  struct sembuf op = {.sem_num = (ipc != &env->me_lck->mti_wlock),
+    *ipc = 0;
-                      .sem_op = 1,
+    struct sembuf op = {.sem_num = (ipc != &env->me_lck->mti_wlock),
-                      .sem_flg = SEM_UNDO};
+                        .sem_op = 1,
-  int rc = semop(env->me_sysv_ipc.semid, &op, 1) ? errno : MDBX_SUCCESS;
+                        .sem_flg = SEM_UNDO};
+    err = semop(env->me_sysv_ipc.semid, &op, 1) ? errno : MDBX_SUCCESS;
+  }
 #else
 #error "FIXME"
 #endif /* MDBX_LOCKING */
+  int rc = err;
+  if (unlikely(rc != MDBX_SUCCESS)) {
+    const uint32_t current_pid = osal_getpid();
+    if (current_pid == env->me_pid || LOG_ENABLED(MDBX_LOG_NOTICE))
+      debug_log((current_pid == env->me_pid)
+                    ? MDBX_LOG_FATAL
+                    : (rc = MDBX_SUCCESS, MDBX_LOG_NOTICE),
+                "ipc-unlock()", __LINE__, "failed: env %p, lck-%s %p, err %d\n",
+                __Wpedantic_format_voidptr(env),
+                (env->me_lck == env->me_lck_mmap.lck) ? "mmap" : "stub",
+                __Wpedantic_format_voidptr(env->me_lck), err);
+  }
   return rc;
 }
 
 MDBX_INTERNAL_FUNC int osal_rdt_lock(MDBX_env *env) {
   TRACE("%s", ">>");
   jitter4testing(true);
-  int rc = mdbx_ipclock_lock(env, &env->me_lck->mti_rlock, false);
+  int rc = osal_ipclock_lock(env, &env->me_lck->mti_rlock, false);
   TRACE("<< rc %d", rc);
   return rc;
 }
 
 MDBX_INTERNAL_FUNC void osal_rdt_unlock(MDBX_env *env) {
   TRACE("%s", ">>");
-  int rc = mdbx_ipclock_unlock(env, &env->me_lck->mti_rlock);
+  int err = osal_ipclock_unlock(env, &env->me_lck->mti_rlock);
-  TRACE("<< rc %d", rc);
+  TRACE("<< err %d", err);
-  if (unlikely(rc != MDBX_SUCCESS))
+  if (unlikely(err != MDBX_SUCCESS))
-    mdbx_panic("%s() failed: err %d\n", __func__, rc);
+    mdbx_panic("%s() failed: err %d\n", __func__, err);
   jitter4testing(true);
 }
 
-int mdbx_txn_lock(MDBX_env *env, bool dont_wait) {
+int osal_txn_lock(MDBX_env *env, bool dont_wait) {
   TRACE("%swait %s", dont_wait ? "dont-" : "", ">>");
   jitter4testing(true);
-  int rc = mdbx_ipclock_lock(env, &env->me_lck->mti_wlock, dont_wait);
+  const int err = osal_ipclock_lock(env, &env->me_lck->mti_wlock, dont_wait);
-  TRACE("<< rc %d", rc);
+  int rc = err;
-  return MDBX_IS_ERROR(rc) ? rc : MDBX_SUCCESS;
+  if (likely(!MDBX_IS_ERROR(err))) {
+    eASSERT(env, !env->me_txn0->mt_owner ||
+                     err == /* если другой поток в этом-же процессе завершился
+                               не освободив блокировку */
+                         MDBX_RESULT_TRUE);
+    env->me_txn0->mt_owner = osal_thread_self();
+    rc = MDBX_SUCCESS;
+  }
+  TRACE("<< err %d, rc %d", err, rc);
+  return rc;
 }
 
-void mdbx_txn_unlock(MDBX_env *env) {
+void osal_txn_unlock(MDBX_env *env) {
   TRACE("%s", ">>");
-  int rc = mdbx_ipclock_unlock(env, &env->me_lck->mti_wlock);
+  eASSERT(env, env->me_txn0->mt_owner == osal_thread_self());
-  TRACE("<< rc %d", rc);
+  env->me_txn0->mt_owner = 0;
-  if (unlikely(rc != MDBX_SUCCESS))
+  int err = osal_ipclock_unlock(env, &env->me_lck->mti_wlock);
-    mdbx_panic("%s() failed: err %d\n", __func__, rc);
+  TRACE("<< err %d", err);
+  if (unlikely(err != MDBX_SUCCESS))
+    mdbx_panic("%s() failed: err %d\n", __func__, err);
   jitter4testing(true);
 }
 

src/lck-windows.c

@@ -178,7 +178,7 @@ static int funlock(mdbx_filehandle_t fd, size_t offset, size_t bytes) {
 #define DXB_BODY (env->me_psize * (size_t)NUM_METAS), DXB_MAXLEN
 #define DXB_WHOLE 0, DXB_MAXLEN
 
-int mdbx_txn_lock(MDBX_env *env, bool dontwait) {
+int osal_txn_lock(MDBX_env *env, bool dontwait) {
   if (dontwait) {
     if (!TryEnterCriticalSection(&env->me_windowsbug_lock))
       return MDBX_BUSY;
@@ -190,16 +190,13 @@ int mdbx_txn_lock(MDBX_env *env, bool dontwait) {
                  0xC0000194 /* STATUS_POSSIBLE_DEADLOCK / EXCEPTION_POSSIBLE_DEADLOCK */)
                     ? EXCEPTION_EXECUTE_HANDLER
                     : EXCEPTION_CONTINUE_SEARCH) {
-      return ERROR_POSSIBLE_DEADLOCK;
+      return MDBX_EDEADLK;
     }
   }
 
-  if (env->me_flags & MDBX_EXCLUSIVE) {
+  eASSERT(env, !env->me_txn0->mt_owner);
-    /* Zap: Failing to release lock 'env->me_windowsbug_lock'
+  if (env->me_flags & MDBX_EXCLUSIVE)
-     *      in function 'mdbx_txn_lock' */
+    goto done;
-    MDBX_SUPPRESS_GOOFY_MSVC_ANALYZER(26115);
-    return MDBX_SUCCESS;
-  }
 
   const HANDLE fd4data =
       env->me_overlapped_fd ? env->me_overlapped_fd : env->me_lazy_fd;
@@ -218,17 +215,20 @@ int mdbx_txn_lock(MDBX_env *env, bool dontwait) {
     }
   }
   if (rc == MDBX_SUCCESS) {
+  done:
     /* Zap: Failing to release lock 'env->me_windowsbug_lock'
      *      in function 'mdbx_txn_lock' */
     MDBX_SUPPRESS_GOOFY_MSVC_ANALYZER(26115);
-    return rc;
+    env->me_txn0->mt_owner = osal_thread_self();
+    return MDBX_SUCCESS;
   }
 
   LeaveCriticalSection(&env->me_windowsbug_lock);
   return (!dontwait || rc != ERROR_LOCK_VIOLATION) ? rc : MDBX_BUSY;
 }
 
-void mdbx_txn_unlock(MDBX_env *env) {
+void osal_txn_unlock(MDBX_env *env) {
+  eASSERT(env, env->me_txn0->mt_owner == osal_thread_self());
   if ((env->me_flags & MDBX_EXCLUSIVE) == 0) {
     const HANDLE fd4data =
         env->me_overlapped_fd ? env->me_overlapped_fd : env->me_lazy_fd;
@@ -236,6 +236,7 @@ void mdbx_txn_unlock(MDBX_env *env) {
     if (err != MDBX_SUCCESS)
       mdbx_panic("%s failed: err %u", __func__, err);
   }
+  env->me_txn0->mt_owner = 0;
   LeaveCriticalSection(&env->me_windowsbug_lock);
 }
 
@@ -442,7 +443,7 @@ osal_resume_threads_after_remap(mdbx_handle_array_t *array) {
  *  The osal_lck_downgrade() moves the locking-FSM from "exclusive write"
  *  state to the "used" (i.e. shared) state.
  *
- *  The mdbx_lck_upgrade() moves the locking-FSM from "used" (i.e. shared)
+ *  The osal_lck_upgrade() moves the locking-FSM from "used" (i.e. shared)
  *  state to the "exclusive write" state.
  */
 
@@ -615,7 +616,7 @@ MDBX_INTERNAL_FUNC int osal_lck_downgrade(MDBX_env *env) {
   return MDBX_SUCCESS /* 5) now at S-? (used), done */;
 }
 
-MDBX_INTERNAL_FUNC int mdbx_lck_upgrade(MDBX_env *env) {
+MDBX_INTERNAL_FUNC int osal_lck_upgrade(MDBX_env *env, bool dont_wait) {
   /* Transite from used state (S-?) to exclusive-write (E-E) */
   assert(env->me_lfd != INVALID_HANDLE_VALUE);
 
@@ -625,7 +626,9 @@ MDBX_INTERNAL_FUNC int mdbx_lck_upgrade(MDBX_env *env) {
 
   /* 1) now on S-? (used), try S-E (locked) */
   jitter4testing(false);
-  int rc = flock(env->me_lfd, LCK_EXCLUSIVE | LCK_DONTWAIT, LCK_UPPER);
+  int rc = flock(env->me_lfd,
+                 dont_wait ? LCK_EXCLUSIVE | LCK_DONTWAIT : LCK_EXCLUSIVE,
+                 LCK_UPPER);
   if (rc != MDBX_SUCCESS) {
     /* 2) something went wrong, give up */;
     VERBOSE("%s, err %u", "S-?(used) >> S-E(locked)", rc);
@@ -640,7 +643,9 @@ MDBX_INTERNAL_FUNC int mdbx_lck_upgrade(MDBX_env *env) {
 
   /* 4) now on ?-E (middle), try E-E (exclusive-write) */
   jitter4testing(false);
-  rc = flock(env->me_lfd, LCK_EXCLUSIVE | LCK_DONTWAIT, LCK_LOWER);
+  rc = flock(env->me_lfd,
+             dont_wait ? LCK_EXCLUSIVE | LCK_DONTWAIT : LCK_EXCLUSIVE,
+             LCK_LOWER);
   if (rc != MDBX_SUCCESS) {
     /* 5) something went wrong, give up */;
     VERBOSE("%s, err %u", "?-E(middle) >> E-E(exclusive-write)", rc);
@@ -677,7 +682,9 @@ MDBX_INTERNAL_FUNC int osal_lck_init(MDBX_env *env,
 }
 
 MDBX_INTERNAL_FUNC int osal_lck_destroy(MDBX_env *env,
-                                        MDBX_env *inprocess_neighbor) {
+                                        MDBX_env *inprocess_neighbor,
+                                        const uint32_t current_pid) {
+  (void)current_pid;
   /* LY: should unmap before releasing the locks to avoid race condition and
    * STATUS_USER_MAPPED_FILE/ERROR_USER_MAPPED_FILE */
   if (env->me_map)
@@ -686,7 +693,7 @@ MDBX_INTERNAL_FUNC int osal_lck_destroy(MDBX_env *env,
     const bool synced = env->me_lck_mmap.lck->mti_unsynced_pages.weak == 0;
     osal_munmap(&env->me_lck_mmap);
     if (synced && !inprocess_neighbor && env->me_lfd != INVALID_HANDLE_VALUE &&
-        mdbx_lck_upgrade(env) == MDBX_SUCCESS)
+        osal_lck_upgrade(env, true) == MDBX_SUCCESS)
       /* this will fail if LCK is used/mmapped by other process(es) */
       osal_ftruncate(env->me_lfd, 0);
   }

src/man1/mdbx_chk.1

@@ -1,6 +1,6 @@
 .\" Copyright 2015-2024 Leonid Yuriev <leo@yuriev.ru>.
 .\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
-.TH MDBX_CHK 1 "2024-03-13" "MDBX 0.12.10"
+.TH MDBX_CHK 1 "2024-03-21" "MDBX 0.13"
 .SH NAME
 mdbx_chk \- MDBX checking tool
 .SH SYNOPSIS

src/man1/mdbx_copy.1

@@ -2,7 +2,7 @@
 .\" Copyright 2015,2016 Peter-Service R&D LLC <http://billing.ru/>.
 .\" Copyright 2012-2015 Howard Chu, Symas Corp. All Rights Reserved.
 .\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
-.TH MDBX_COPY 1 "2024-03-13" "MDBX 0.12.10"
+.TH MDBX_COPY 1 "2024-03-21" "MDBX 0.13"
 .SH NAME
 mdbx_copy \- MDBX environment copy tool
 .SH SYNOPSIS

src/man1/mdbx_drop.1

@@ -1,7 +1,7 @@
 .\" Copyright 2021-2024 Leonid Yuriev <leo@yuriev.ru>.
 .\" Copyright 2014-2021 Howard Chu, Symas Corp. All Rights Reserved.
 .\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
-.TH MDBX_DROP 1 "2024-03-13" "MDBX 0.12.10"
+.TH MDBX_DROP 1 "2024-03-21" "MDBX 0.13"
 .SH NAME
 mdbx_drop \- MDBX database delete tool
 .SH SYNOPSIS

src/man1/mdbx_dump.1

@@ -2,7 +2,7 @@
 .\" Copyright 2015,2016 Peter-Service R&D LLC <http://billing.ru/>.
 .\" Copyright 2014-2015 Howard Chu, Symas Corp. All Rights Reserved.
 .\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
-.TH MDBX_DUMP 1 "2024-03-13" "MDBX 0.12.10"
+.TH MDBX_DUMP 1 "2024-03-21" "MDBX 0.13"
 .SH NAME
 mdbx_dump \- MDBX environment export tool
 .SH SYNOPSIS

src/man1/mdbx_load.1

@@ -2,7 +2,7 @@
 .\" Copyright 2015,2016 Peter-Service R&D LLC <http://billing.ru/>.
 .\" Copyright 2014-2015 Howard Chu, Symas Corp. All Rights Reserved.
 .\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
-.TH MDBX_LOAD 1 "2024-03-13" "MDBX 0.12.10"
+.TH MDBX_LOAD 1 "2024-03-21" "MDBX 0.13"
 .SH NAME
 mdbx_load \- MDBX environment import tool
 .SH SYNOPSIS

src/man1/mdbx_stat.1

@@ -2,7 +2,7 @@
 .\" Copyright 2015,2016 Peter-Service R&D LLC <http://billing.ru/>.
 .\" Copyright 2012-2015 Howard Chu, Symas Corp. All Rights Reserved.
 .\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
-.TH MDBX_STAT 1 "2024-03-13" "MDBX 0.12.10"
+.TH MDBX_STAT 1 "2024-03-21" "MDBX 0.13"
 .SH NAME
 mdbx_stat \- MDBX environment status tool
 .SH SYNOPSIS

src/mdbx.c++

@@ -271,6 +271,11 @@ namespace mdbx {
       "into an incompatible memory allocation scheme.");
 }
 
+[[noreturn]] __cold void throw_incomparable_cursors() {
+  throw std::logic_error(
+      "mdbx:: incomparable and/or invalid cursors to compare positions.");
+}
+
 [[noreturn]] __cold void throw_bad_value_size() {
   throw bad_value_size(MDBX_BAD_VALSIZE);
 }
@@ -324,6 +329,8 @@ DEFINE_EXCEPTION(thread_mismatch)
 DEFINE_EXCEPTION(transaction_full)
 DEFINE_EXCEPTION(transaction_overlapping)
 DEFINE_EXCEPTION(duplicated_lck_file)
+DEFINE_EXCEPTION(dangling_map_id)
+
 #undef DEFINE_EXCEPTION
 
 __cold const char *error::what() const noexcept {
@@ -410,6 +417,7 @@ __cold void error::throw_exception() const {
     CASE_EXCEPTION(transaction_full, MDBX_TXN_FULL);
     CASE_EXCEPTION(transaction_overlapping, MDBX_TXN_OVERLAPPING);
     CASE_EXCEPTION(duplicated_lck_file, MDBX_DUPLICATED_CLK);
+    CASE_EXCEPTION(dangling_map_id, MDBX_DANGLING_DBI);
 #undef CASE_EXCEPTION
   default:
     if (is_mdbx_error())
@@ -527,48 +535,48 @@ bool slice::is_printable(bool disable_utf8) const noexcept {
 }
 
 #ifdef MDBX_U128_TYPE
-MDBX_U128_TYPE slice::as_uint128() const {
+MDBX_U128_TYPE slice::as_uint128_adapt() const {
   static_assert(sizeof(MDBX_U128_TYPE) == 16, "WTF?");
   if (size() == 16) {
     MDBX_U128_TYPE r;
     memcpy(&r, data(), sizeof(r));
     return r;
   } else
-    return as_uint64();
+    return as_uint64_adapt();
 }
 #endif /* MDBX_U128_TYPE */
 
-uint64_t slice::as_uint64() const {
+uint64_t slice::as_uint64_adapt() const {
   static_assert(sizeof(uint64_t) == 8, "WTF?");
   if (size() == 8) {
     uint64_t r;
     memcpy(&r, data(), sizeof(r));
     return r;
   } else
-    return as_uint32();
+    return as_uint32_adapt();
 }
 
-uint32_t slice::as_uint32() const {
+uint32_t slice::as_uint32_adapt() const {
   static_assert(sizeof(uint32_t) == 4, "WTF?");
   if (size() == 4) {
     uint32_t r;
     memcpy(&r, data(), sizeof(r));
     return r;
   } else
-    return as_uint16();
+    return as_uint16_adapt();
 }
 
-uint16_t slice::as_uint16() const {
+uint16_t slice::as_uint16_adapt() const {
   static_assert(sizeof(uint16_t) == 2, "WTF?");
   if (size() == 2) {
     uint16_t r;
     memcpy(&r, data(), sizeof(r));
     return r;
   } else
-    return as_uint8();
+    return as_uint8_adapt();
 }
 
-uint8_t slice::as_uint8() const {
+uint8_t slice::as_uint8_adapt() const {
   static_assert(sizeof(uint8_t) == 1, "WTF?");
   if (size() == 1)
     return *static_cast<const uint8_t *>(data());
@@ -579,48 +587,48 @@ uint8_t slice::as_uint8() const {
 }
 
 #ifdef MDBX_I128_TYPE
-MDBX_I128_TYPE slice::as_int128() const {
+MDBX_I128_TYPE slice::as_int128_adapt() const {
   static_assert(sizeof(MDBX_I128_TYPE) == 16, "WTF?");
   if (size() == 16) {
     MDBX_I128_TYPE r;
     memcpy(&r, data(), sizeof(r));
     return r;
   } else
-    return as_int64();
+    return as_int64_adapt();
 }
 #endif /* MDBX_I128_TYPE */
 
-int64_t slice::as_int64() const {
+int64_t slice::as_int64_adapt() const {
   static_assert(sizeof(int64_t) == 8, "WTF?");
   if (size() == 8) {
     uint64_t r;
     memcpy(&r, data(), sizeof(r));
     return r;
   } else
-    return as_int32();
+    return as_int32_adapt();
 }
 
-int32_t slice::as_int32() const {
+int32_t slice::as_int32_adapt() const {
   static_assert(sizeof(int32_t) == 4, "WTF?");
   if (size() == 4) {
     int32_t r;
     memcpy(&r, data(), sizeof(r));
     return r;
   } else
-    return as_int16();
+    return as_int16_adapt();
 }
 
-int16_t slice::as_int16() const {
+int16_t slice::as_int16_adapt() const {
   static_assert(sizeof(int16_t) == 2, "WTF?");
   if (size() == 2) {
     int16_t r;
     memcpy(&r, data(), sizeof(r));
     return r;
   } else
-    return as_int8();
+    return as_int8_adapt();
 }
 
-int8_t slice::as_int8() const {
+int8_t slice::as_int8_adapt() const {
   if (size() == 1)
     return *static_cast<const int8_t *>(data());
   else if (size() == 0)
@@ -1535,6 +1543,13 @@ void txn_managed::commit(commit_latency *latency) {
     MDBX_CXX20_UNLIKELY err.throw_exception();
 }
 
+void txn_managed::commit_embark_read() {
+  auto env = this->env();
+  commit();
+  error::success_or_throw(
+      ::mdbx_txn_begin(env, nullptr, MDBX_TXN_RDONLY, &handle_));
+}
+
 //------------------------------------------------------------------------------
 
 bool txn::drop_map(const char *name, bool throw_if_absent) {

src/mdbx_load.c

@@ -505,7 +505,7 @@ static int equal_or_greater(const MDBX_val *a, const MDBX_val *b) {
 }
 
 int main(int argc, char *argv[]) {
-  int i, rc;
+  int i, err;
   MDBX_env *env = nullptr;
   MDBX_txn *txn = nullptr;
   MDBX_cursor *mc = nullptr;
@@ -608,40 +608,45 @@ int main(int argc, char *argv[]) {
   dbuf.iov_len = 4096;
   dbuf.iov_base = osal_malloc(dbuf.iov_len);
   if (!dbuf.iov_base) {
-    rc = MDBX_ENOMEM;
+    err = MDBX_ENOMEM;
-    error("value-buffer", rc);
+    error("value-buffer", err);
-    goto env_close;
+    goto bailout;
   }
 
   /* read first header for mapsize= */
   if (!(mode & NOHDR)) {
-    rc = readhdr();
+    err = readhdr();
-    if (unlikely(rc != MDBX_SUCCESS)) {
+    if (unlikely(err != MDBX_SUCCESS)) {
-      if (rc == EOF)
+      if (err == EOF)
-        rc = MDBX_ENODATA;
+        err = MDBX_ENODATA;
-      error("readheader", rc);
+      error("readheader", err);
-      goto env_close;
+      goto bailout;
     }
   }
 
-  rc = mdbx_env_create(&env);
+  err = mdbx_env_create(&env);
-  if (unlikely(rc != MDBX_SUCCESS)) {
+  if (unlikely(err != MDBX_SUCCESS)) {
-    error("mdbx_env_create", rc);
+    error("mdbx_env_create", err);
-    return EXIT_FAILURE;
+    goto bailout;
+  }
+
+  err = mdbx_env_set_maxdbs(env, 2);
+  if (unlikely(err != MDBX_SUCCESS)) {
+    error("mdbx_env_set_maxdbs", err);
+    goto bailout;
   }
 
-  mdbx_env_set_maxdbs(env, 2);
   if (envinfo.mi_maxreaders) {
-    rc = mdbx_env_set_maxreaders(env, envinfo.mi_maxreaders);
+    err = mdbx_env_set_maxreaders(env, envinfo.mi_maxreaders);
-    if (unlikely(rc != MDBX_SUCCESS)) {
+    if (unlikely(err != MDBX_SUCCESS)) {
-      error("mdbx_env_set_maxreaders", rc);
+      error("mdbx_env_set_maxreaders", err);
-      goto env_close;
+      goto bailout;
     }
   }
 
   if (envinfo.mi_geo.current | envinfo.mi_mapsize) {
     if (envinfo.mi_geo.current) {
-      rc = mdbx_env_set_geometry(
+      err = mdbx_env_set_geometry(
           env, (intptr_t)envinfo.mi_geo.lower, (intptr_t)envinfo.mi_geo.current,
           (intptr_t)envinfo.mi_geo.upper, (intptr_t)envinfo.mi_geo.shrink,
           (intptr_t)envinfo.mi_geo.grow,
@@ -654,23 +659,23 @@ int main(int argc, char *argv[]) {
               "Database size is too large for current system (mapsize=%" PRIu64
               " is great than system-limit %zu)\n",
               envinfo.mi_mapsize, (size_t)MAX_MAPSIZE);
-        goto env_close;
+        goto bailout;
       }
-      rc = mdbx_env_set_geometry(
+      err = mdbx_env_set_geometry(
           env, (intptr_t)envinfo.mi_mapsize, (intptr_t)envinfo.mi_mapsize,
           (intptr_t)envinfo.mi_mapsize, 0, 0,
           envinfo.mi_dxb_pagesize ? (intptr_t)envinfo.mi_dxb_pagesize : -1);
     }
-    if (unlikely(rc != MDBX_SUCCESS)) {
+    if (unlikely(err != MDBX_SUCCESS)) {
-      error("mdbx_env_set_geometry", rc);
+      error("mdbx_env_set_geometry", err);
-      goto env_close;
+      goto bailout;
     }
   }
 
-  rc = mdbx_env_open(env, envname, envflags, 0664);
+  err = mdbx_env_open(env, envname, envflags, 0664);
-  if (unlikely(rc != MDBX_SUCCESS)) {
+  if (unlikely(err != MDBX_SUCCESS)) {
-    error("mdbx_env_open", rc);
+    error("mdbx_env_open", err);
-    goto env_close;
+    goto bailout;
   }
 
   kbuf.iov_len = mdbx_env_get_maxvalsize_ex(env, 0) + (size_t)1;
@@ -678,54 +683,54 @@ int main(int argc, char *argv[]) {
     if (!quiet)
       fprintf(stderr, "mdbx_env_get_maxkeysize() failed, returns %zu\n",
               kbuf.iov_len);
-    goto env_close;
+    goto bailout;
   }
 
   kbuf.iov_base = malloc(kbuf.iov_len);
   if (!kbuf.iov_base) {
-    rc = MDBX_ENOMEM;
+    err = MDBX_ENOMEM;
-    error("key-buffer", rc);
+    error("key-buffer", err);
-    goto env_close;
+    goto bailout;
   }
 
-  while (rc == MDBX_SUCCESS) {
+  while (err == MDBX_SUCCESS) {
     if (user_break) {
-      rc = MDBX_EINTR;
+      err = MDBX_EINTR;
       break;
     }
 
-    rc = mdbx_txn_begin(env, nullptr, 0, &txn);
+    err = mdbx_txn_begin(env, nullptr, 0, &txn);
-    if (unlikely(rc != MDBX_SUCCESS)) {
+    if (unlikely(err != MDBX_SUCCESS)) {
-      error("mdbx_txn_begin", rc);
+      error("mdbx_txn_begin", err);
-      goto env_close;
+      goto bailout;
     }
 
     if (mode & GLOBAL) {
       mode -= GLOBAL;
       if (canary.v | canary.x | canary.y | canary.z) {
-        rc = mdbx_canary_put(txn, &canary);
+        err = mdbx_canary_put(txn, &canary);
-        if (unlikely(rc != MDBX_SUCCESS)) {
+        if (unlikely(err != MDBX_SUCCESS)) {
-          error("mdbx_canary_put", rc);
+          error("mdbx_canary_put", err);
-          goto txn_abort;
+          goto bailout;
         }
       }
     }
 
     const char *const dbi_name = subname ? subname : "@MAIN";
-    rc =
+    err =
         mdbx_dbi_open_ex(txn, subname, dbi_flags | MDBX_CREATE, &dbi,
                          (putflags & MDBX_APPEND) ? equal_or_greater : nullptr,
                          (putflags & MDBX_APPEND) ? equal_or_greater : nullptr);
-    if (unlikely(rc != MDBX_SUCCESS)) {
+    if (unlikely(err != MDBX_SUCCESS)) {
-      error("mdbx_dbi_open_ex", rc);
+      error("mdbx_dbi_open_ex", err);
-      goto txn_abort;
+      goto bailout;
     }
 
     uint64_t present_sequence;
-    rc = mdbx_dbi_sequence(txn, dbi, &present_sequence, 0);
+    err = mdbx_dbi_sequence(txn, dbi, &present_sequence, 0);
-    if (unlikely(rc != MDBX_SUCCESS)) {
+    if (unlikely(err != MDBX_SUCCESS)) {
-      error("mdbx_dbi_sequence", rc);
+      error("mdbx_dbi_sequence", err);
-      goto txn_abort;
+      goto bailout;
     }
     if (present_sequence > sequence) {
       if (!quiet)
@@ -733,22 +738,22 @@ int main(int argc, char *argv[]) {
                 "present sequence for '%s' value (%" PRIu64
                 ") is greater than loaded (%" PRIu64 ")\n",
                 dbi_name, present_sequence, sequence);
-      rc = MDBX_RESULT_TRUE;
+      err = MDBX_RESULT_TRUE;
-      goto txn_abort;
+      goto bailout;
     }
     if (present_sequence < sequence) {
-      rc = mdbx_dbi_sequence(txn, dbi, nullptr, sequence - present_sequence);
+      err = mdbx_dbi_sequence(txn, dbi, nullptr, sequence - present_sequence);
-      if (unlikely(rc != MDBX_SUCCESS)) {
+      if (unlikely(err != MDBX_SUCCESS)) {
-        error("mdbx_dbi_sequence", rc);
+        error("mdbx_dbi_sequence", err);
-        goto txn_abort;
+        goto bailout;
       }
     }
 
     if (purge) {
-      rc = mdbx_drop(txn, dbi, false);
+      err = mdbx_drop(txn, dbi, false);
-      if (unlikely(rc != MDBX_SUCCESS)) {
+      if (unlikely(err != MDBX_SUCCESS)) {
-        error("mdbx_drop", rc);
+        error("mdbx_drop", err);
-        goto txn_abort;
+        goto bailout;
       }
     }
 
@@ -756,85 +761,85 @@ int main(int argc, char *argv[]) {
       putflags = (dbi_flags & MDBX_DUPSORT) ? putflags | MDBX_APPENDDUP
                                             : putflags & ~MDBX_APPENDDUP;
 
-    rc = mdbx_cursor_open(txn, dbi, &mc);
+    err = mdbx_cursor_open(txn, dbi, &mc);
-    if (unlikely(rc != MDBX_SUCCESS)) {
+    if (unlikely(err != MDBX_SUCCESS)) {
-      error("mdbx_cursor_open", rc);
+      error("mdbx_cursor_open", err);
-      goto txn_abort;
+      goto bailout;
     }
 
     int batch = 0;
-    while (rc == MDBX_SUCCESS) {
+    while (err == MDBX_SUCCESS) {
       MDBX_val key, data;
-      rc = readline(&key, &kbuf);
+      err = readline(&key, &kbuf);
-      if (rc == EOF)
+      if (err == EOF)
         break;
 
-      if (rc == MDBX_SUCCESS)
+      if (err == MDBX_SUCCESS)
-        rc = readline(&data, &dbuf);
+        err = readline(&data, &dbuf);
-      if (rc) {
+      if (err) {
         if (!quiet)
           fprintf(stderr, "%s: line %" PRIiSIZE ": failed to read key value\n",
                   prog, lineno);
-        goto txn_abort;
+        goto bailout;
       }
 
-      rc = mdbx_cursor_put(mc, &key, &data, putflags);
+      err = mdbx_cursor_put(mc, &key, &data, putflags);
-      if (rc == MDBX_KEYEXIST && putflags)
+      if (err == MDBX_KEYEXIST && putflags)
         continue;
-      if (rc == MDBX_BAD_VALSIZE && rescue) {
+      if (err == MDBX_BAD_VALSIZE && rescue) {
         if (!quiet)
           fprintf(stderr, "%s: skip line %" PRIiSIZE ": due %s\n", prog, lineno,
-                  mdbx_strerror(rc));
+                  mdbx_strerror(err));
         continue;
       }
-      if (unlikely(rc != MDBX_SUCCESS)) {
+      if (unlikely(err != MDBX_SUCCESS)) {
-        error("mdbx_cursor_put", rc);
+        error("mdbx_cursor_put", err);
-        goto txn_abort;
+        goto bailout;
       }
       batch++;
 
       MDBX_txn_info txn_info;
-      rc = mdbx_txn_info(txn, &txn_info, false);
+      err = mdbx_txn_info(txn, &txn_info, false);
-      if (unlikely(rc != MDBX_SUCCESS)) {
+      if (unlikely(err != MDBX_SUCCESS)) {
-        error("mdbx_txn_info", rc);
+        error("mdbx_txn_info", err);
-        goto txn_abort;
+        goto bailout;
       }
 
       if (batch == 10000 || txn_info.txn_space_dirty > MEGABYTE * 256) {
-        rc = mdbx_txn_commit(txn);
+        err = mdbx_txn_commit(txn);
-        if (unlikely(rc != MDBX_SUCCESS)) {
+        if (unlikely(err != MDBX_SUCCESS)) {
-          error("mdbx_txn_commit", rc);
+          error("mdbx_txn_commit", err);
-          goto env_close;
+          goto bailout;
         }
         batch = 0;
 
-        rc = mdbx_txn_begin(env, nullptr, 0, &txn);
+        err = mdbx_txn_begin(env, nullptr, 0, &txn);
-        if (unlikely(rc != MDBX_SUCCESS)) {
+        if (unlikely(err != MDBX_SUCCESS)) {
-          error("mdbx_txn_begin", rc);
+          error("mdbx_txn_begin", err);
-          goto env_close;
+          goto bailout;
         }
-        rc = mdbx_cursor_bind(txn, mc, dbi);
+        err = mdbx_cursor_bind(txn, mc, dbi);
-        if (unlikely(rc != MDBX_SUCCESS)) {
+        if (unlikely(err != MDBX_SUCCESS)) {
-          error("mdbx_cursor_bind", rc);
+          error("mdbx_cursor_bind", err);
-          goto txn_abort;
+          goto bailout;
         }
       }
     }
 
     mdbx_cursor_close(mc);
     mc = nullptr;
-    rc = mdbx_txn_commit(txn);
+    err = mdbx_txn_commit(txn);
     txn = nullptr;
-    if (unlikely(rc != MDBX_SUCCESS)) {
+    if (unlikely(err != MDBX_SUCCESS)) {
-      error("mdbx_txn_commit", rc);
+      error("mdbx_txn_commit", err);
-      goto env_close;
+      goto bailout;
     }
     if (subname) {
       assert(dbi != MAIN_DBI);
-      rc = mdbx_dbi_close(env, dbi);
+      err = mdbx_dbi_close(env, dbi);
-      if (unlikely(rc != MDBX_SUCCESS)) {
+      if (unlikely(err != MDBX_SUCCESS)) {
-        error("mdbx_dbi_close", rc);
+        error("mdbx_dbi_close", err);
-        goto env_close;
+        goto bailout;
       }
     } else {
       assert(dbi == MAIN_DBI);
@@ -842,14 +847,14 @@ int main(int argc, char *argv[]) {
 
     /* try read next header */
     if (!(mode & NOHDR))
-      rc = readhdr();
+      err = readhdr();
     else if (ferror(stdin) || feof(stdin))
       break;
   }
 
-  switch (rc) {
+  switch (err) {
   case EOF:
-    rc = MDBX_SUCCESS;
+    err = MDBX_SUCCESS;
   case MDBX_SUCCESS:
     break;
   case MDBX_EINTR:
@@ -857,17 +862,19 @@ int main(int argc, char *argv[]) {
       fprintf(stderr, "Interrupted by signal/user\n");
     break;
   default:
-    if (unlikely(rc != MDBX_SUCCESS))
+    if (unlikely(err != MDBX_SUCCESS))
-      error("readline", rc);
+      error("readline", err);
   }
 
-txn_abort:
+bailout:
-  mdbx_cursor_close(mc);
+  if (mc)
-  mdbx_txn_abort(txn);
+    mdbx_cursor_close(mc);
-env_close:
+  if (txn)
-  mdbx_env_close(env);
+    mdbx_txn_abort(txn);
+  if (env)
+    mdbx_env_close(env);
   free(kbuf.iov_base);
   free(dbuf.iov_base);
 
-  return rc ? EXIT_FAILURE : EXIT_SUCCESS;
+  return err ? EXIT_FAILURE : EXIT_SUCCESS;
 }

src/options.h

@@ -164,6 +164,20 @@
 #error MDBX_AVOID_MSYNC must be defined as 0 or 1
 #endif /* MDBX_AVOID_MSYNC */
 
+/** FIXME */
+#ifndef MDBX_ENABLE_DBI_SPARSE
+#define MDBX_ENABLE_DBI_SPARSE 1
+#elif !(MDBX_ENABLE_DBI_SPARSE == 0 || MDBX_ENABLE_DBI_SPARSE == 1)
+#error MDBX_ENABLE_DBI_SPARSE must be defined as 0 or 1
+#endif /* MDBX_ENABLE_DBI_SPARSE */
+
+/** FIXME */
+#ifndef MDBX_ENABLE_DBI_LOCKFREE
+#define MDBX_ENABLE_DBI_LOCKFREE 1
+#elif !(MDBX_ENABLE_DBI_LOCKFREE == 0 || MDBX_ENABLE_DBI_LOCKFREE == 1)
+#error MDBX_ENABLE_DBI_LOCKFREE must be defined as 0 or 1
+#endif /* MDBX_ENABLE_DBI_LOCKFREE */
+
 /** Controls sort order of internal page number lists.
  * This mostly experimental/advanced option with not for regular MDBX users.
  * \warning The database format depend on this option and libmdbx built with
@@ -211,8 +225,8 @@
 
 /** If defined then enables integration with Valgrind,
  * a memory analyzing tool. */
-#ifndef MDBX_USE_VALGRIND
+#ifndef ENABLE_MEMCHECK
-#endif /* MDBX_USE_VALGRIND */
+#endif /* ENABLE_MEMCHECK */
 
 /** If defined then enables use C11 atomics,
  *  otherwise detects ones availability automatically. */

src/osal.c

@@ -503,8 +503,18 @@ MDBX_INTERNAL_FUNC int osal_fastmutex_init(osal_fastmutex_t *fastmutex) {
 #if defined(_WIN32) || defined(_WIN64)
   InitializeCriticalSection(fastmutex);
   return MDBX_SUCCESS;
+#elif MDBX_DEBUG
+  pthread_mutexattr_t ma;
+  int rc = pthread_mutexattr_init(&ma);
+  if (likely(!rc)) {
+    rc = pthread_mutexattr_settype(&ma, PTHREAD_MUTEX_ERRORCHECK);
+    if (likely(!rc) || rc == ENOTSUP)
+      rc = pthread_mutex_init(fastmutex, &ma);
+    pthread_mutexattr_destroy(&ma);
+  }
+  return rc;
 #else
-  return pthread_mutex_init(fastmutex, NULL);
+  return pthread_mutex_init(fastmutex, nullptr);
 #endif
 }
 
@@ -526,7 +536,7 @@ MDBX_INTERNAL_FUNC int osal_fastmutex_acquire(osal_fastmutex_t *fastmutex) {
        0xC0000194 /* STATUS_POSSIBLE_DEADLOCK / EXCEPTION_POSSIBLE_DEADLOCK */)
           ? EXCEPTION_EXECUTE_HANDLER
           : EXCEPTION_CONTINUE_SEARCH) {
-    return ERROR_POSSIBLE_DEADLOCK;
+    return MDBX_EDEADLK;
   }
   return MDBX_SUCCESS;
 #else

src/osal.h

@@ -690,7 +690,8 @@ MDBX_INTERNAL_FUNC int osal_lck_init(MDBX_env *env,
 ///     restore POSIX-fcntl locks after the closing of file descriptors.
 /// \return Error code (MDBX_PANIC) or zero on success.
 MDBX_INTERNAL_FUNC int osal_lck_destroy(MDBX_env *env,
-                                        MDBX_env *inprocess_neighbor);
+                                        MDBX_env *inprocess_neighbor,
+                                        const uint32_t current_pid);
 
 /// \brief Connects to shared interprocess locking objects and tries to acquire
 ///   the maximum lock level (shared if exclusive is not available)
@@ -718,6 +719,8 @@ MDBX_INTERNAL_FUNC int osal_lck_seize(MDBX_env *env);
 ///   operational lock.
 /// \return Error code or zero on success
 MDBX_INTERNAL_FUNC int osal_lck_downgrade(MDBX_env *env);
+MDBX_MAYBE_UNUSED MDBX_INTERNAL_FUNC int osal_lck_upgrade(MDBX_env *env,
+                                                          bool dont_wait);
 
 /// \brief Locks LCK-file or/and table of readers for (de)registering.
 /// \return Error code or zero on success
@@ -726,16 +729,12 @@ MDBX_INTERNAL_FUNC int osal_rdt_lock(MDBX_env *env);
 /// \brief Unlocks LCK-file or/and table of readers after (de)registering.
 MDBX_INTERNAL_FUNC void osal_rdt_unlock(MDBX_env *env);
 
-/// \brief Acquires lock for DB change (on writing transaction start)
+/// \brief Acquires write-transaction lock.
-///   Reading transactions will not be blocked.
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
 /// \return Error code or zero on success
-LIBMDBX_API int mdbx_txn_lock(MDBX_env *env, bool dont_wait);
+MDBX_INTERNAL_FUNC int osal_txn_lock(MDBX_env *env, bool dont_wait);
 
-/// \brief Releases lock once DB changes is made (after writing transaction
+/// \brief Releases write-transaction lock..
-///   has finished).
+MDBX_INTERNAL_FUNC void osal_txn_unlock(MDBX_env *env);
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-LIBMDBX_API void mdbx_txn_unlock(MDBX_env *env);
 
 /// \brief Sets alive-flag of reader presence (indicative lock) for PID of
 ///   the current process. The function does no more than needed for

test/CMakeLists.txt

@@ -28,6 +28,7 @@ set(LIBMDBX_TEST_SOURCES
   append.c++
   ttl.c++
   nested.c++
+  fork.c++
   )
 
 if(NOT MDBX_BUILD_CXX)
@@ -91,6 +92,20 @@ if(UNIX AND NOT SUBPROJECT)
       set_target_properties(test_extra_dupfixed_multiple PROPERTIES
         CXX_STANDARD ${MDBX_CXX_STANDARD} CXX_STANDARD_REQUIRED ON)
     endif()
+    add_executable(test_extra_hex_base64_base58 extra/hex_base64_base58.c++)
+    target_include_directories(test_extra_hex_base64_base58 PRIVATE "${PROJECT_SOURCE_DIR}")
+    target_link_libraries(test_extra_hex_base64_base58 ${TOOL_MDBX_LIB})
+    if(MDBX_CXX_STANDARD)
+      set_target_properties(test_extra_hex_base64_base58 PROPERTIES
+        CXX_STANDARD ${MDBX_CXX_STANDARD} CXX_STANDARD_REQUIRED ON)
+    endif()
+    add_executable(test_extra_doubtless_positioning extra/doubtless_positioning.c++)
+    target_include_directories(test_extra_doubtless_positioning PRIVATE "${PROJECT_SOURCE_DIR}")
+    target_link_libraries(test_extra_doubtless_positioning ${TOOL_MDBX_LIB})
+    if(MDBX_CXX_STANDARD)
+      set_target_properties(test_extra_doubtless_positioning PROPERTIES
+        CXX_STANDARD ${MDBX_CXX_STANDARD} CXX_STANDARD_REQUIRED ON)
+    endif()
   endif()
 endif()
 
@@ -107,7 +122,7 @@ else()
 
   add_test(NAME smoke COMMAND ${MDBX_OUTPUT_DIR}/mdbx_test
     --loglevel=verbose
-    --keygen.seed=${test_seed}
+    --prng-seed=${test_seed}
     --progress --console=no --pathname=smoke.db --dont-cleanup-after basic)
   set_tests_properties(smoke PROPERTIES
     TIMEOUT 600
@@ -129,11 +144,11 @@ else()
 
   add_test(NAME dupsort_writemap COMMAND ${MDBX_OUTPUT_DIR}/mdbx_test
     --loglevel=notice
-    --keygen.seed=${test_seed}
+    --prng-seed=${test_seed}
-    --table=+data.integer --keygen.split=29 --datalen.min=min --datalen.max=max --progress --console=no
+    --table=+data.fixed --keygen.split=29 --datalen=rnd --progress --console=no
     --repeat=2 --pathname=dupsort_writemap.db --dont-cleanup-after basic)
   set_tests_properties(dupsort_writemap PROPERTIES
-    TIMEOUT 600
+    TIMEOUT 3600
     RUN_SERIAL OFF)
   if(MDBX_BUILD_TOOLS)
     add_test(NAME dupsort_writemap_chk COMMAND ${MDBX_OUTPUT_DIR}/mdbx_chk -nvvwc dupsort_writemap.db)
@@ -176,6 +191,11 @@ else()
     if(MDBX_BUILD_CXX)
       add_test(NAME extra_maindb_ordinal COMMAND test_extra_maindb_ordinal)
       add_test(NAME extra_dupfixed_multiple COMMAND test_extra_dupfixed_multiple)
+      add_test(NAME extra_hex_base64_base58 COMMAND test_extra_hex_base64_base58)
+      add_test(NAME extra_doubtless_positioning COMMAND test_extra_doubtless_positioning)
+      if (ENABLE_MEMCHECK)
+        set_tests_properties(extra_doubtless_positioning PROPERTIES TIMEOUT 10800)
+      endif()
     endif()
   endif()
 

test/append.c++

@@ -20,8 +20,8 @@ public:
       : testcase(config, pid) {}
   bool run() override;
 
-  static bool review_params(actor_params &params) {
+  static bool review_params(actor_params &params, unsigned space_id) {
-    if (!testcase::review_params(params))
+    if (!testcase::review_params(params, space_id))
       return false;
     const bool ordered = !flipcoin_x3();
     log_notice("the '%s' key-generation mode is selected",
@@ -45,7 +45,7 @@ bool testcase_append::run() {
   }
 
   cursor_open(dbi);
-  keyvalue_maker.setup(config.params, config.actor_id, 0 /* thread_number */);
+  keyvalue_maker.setup(config.params, 0 /* thread_number */);
   /* LY: тест наполнения таблиц в append-режиме,
    * при котором записи добавляются строго в конец (в порядке сортировки) */
   const MDBX_put_flags_t flags =

test/cases.c++

@@ -41,8 +41,9 @@ testcase *registry::create_actor(const actor_config &config,
 }
 
 bool registry::review_actor_params(const actor_testcase id,
-                                   actor_params &params) {
+                                   actor_params &params,
-  return instance()->id2record.at(id)->review_params(params);
+                                   const unsigned space_id) {
+  return instance()->id2record.at(id)->review_params(params, space_id);
 }
 
 //-----------------------------------------------------------------------------
@@ -78,13 +79,13 @@ void configure_actor(unsigned &last_space_id, const actor_testcase testcase,
       failure("The '%s' is unexpected for space-id\n", end);
   }
 
-  if (!registry::review_actor_params(testcase, params))
-    failure("Actor config-review failed for space-id %lu\n", space_id);
-
   if (space_id > ACTOR_ID_MAX)
     failure("Invalid space-id %lu\n", space_id);
-  last_space_id = unsigned(space_id);
 
+  if (!registry::review_actor_params(testcase, params, unsigned(space_id)))
+    failure("Actor config-review failed for space-id %lu\n", space_id);
+
+  last_space_id = unsigned(space_id);
   log_trace("configure_actor: space %lu for %s", space_id,
             testcase2str(testcase));
   global::actors.emplace_back(
@@ -105,6 +106,10 @@ void testcase_setup(const char *casename, const actor_params &params,
     configure_actor(last_space_id, ac_try, nullptr, params);
     configure_actor(last_space_id, ac_jitter, nullptr, params);
     configure_actor(last_space_id, ac_try, nullptr, params);
+#if !defined(_WIN32) && !defined(_WIN64)
+    configure_actor(last_space_id, ac_forkread, nullptr, params);
+    configure_actor(last_space_id, ac_forkwrite, nullptr, params);
+#endif /* Windows */
     log_notice("<<< testcase_setup(%s): done", casename);
   } else {
     failure("unknown testcase `%s`", casename);

test/config.c++

@@ -145,6 +145,16 @@ bool parse_option(int argc, char *const argv[], int &narg, const char *option,
     return true;
   }
 
+  if (strcmp(value_cstr, "rnd") == 0 || strcmp(value_cstr, "rand") == 0 ||
+      strcmp(value_cstr, "random") == 0) {
+    value = minval;
+    if (maxval > minval)
+      value += (prng32() + UINT64_C(44263400549519813)) % (maxval - minval);
+    if (scale == intkey)
+      value &= ~3u;
+    return true;
+  }
+
   char *suffix = nullptr;
   errno = 0;
   unsigned long long raw = strtoull(value_cstr, &suffix, 0);
@@ -159,7 +169,7 @@ bool parse_option(int argc, char *const argv[], int &narg, const char *option,
 
   uint64_t multiplier = 1;
   if (suffix && *suffix) {
-    if (scale == no_scale)
+    if (scale == no_scale || scale == intkey)
       failure("Option '--%s' doesn't accepts suffixes, so '%s' is unexpected\n",
               option, suffix);
     if (strcmp(suffix, "K") == 0 || strcasecmp(suffix, "Kilo") == 0)
@@ -203,6 +213,8 @@ bool parse_option(int argc, char *const argv[], int &narg, const char *option,
   if (value < minval)
     failure("The minimal value for option '--%s' is %" PRIu64 "\n", option,
             minval);
+  if (scale == intkey)
+    value &= ~3u;
   return true;
 }
 
@@ -422,6 +434,7 @@ void dump(const char *title) {
     log_verbose("#%u, testcase %s, space_id/table %u\n", i->actor_id,
                 testcase2str(i->testcase), i->space_id);
     indent.push();
+    log_verbose("prng-seed: %u\n", i->params.prng_seed);
 
     if (i->params.loglevel) {
       log_verbose("log: level %u, %s\n", i->params.loglevel,
@@ -461,7 +474,6 @@ void dump(const char *title) {
         i->params.keygen.mesh, i->params.keygen.rotate, i->params.keygen.offset,
         i->params.keygen.split,
         i->params.keygen.width - i->params.keygen.split);
-    log_verbose("keygen.seed: %u\n", i->params.keygen.seed);
     log_verbose("keygen.zerofill: %s\n",
                 i->params.keygen.zero_fill ? "Yes" : "No");
     log_verbose("key: minlen %u, maxlen %u\n", i->params.keylen_min,
@@ -681,7 +693,7 @@ bool actor_config::deserialize(const char *str, actor_config &config) {
 }
 
 unsigned actor_params::mdbx_keylen_min() const {
-  return (table_flags & MDBX_INTEGERKEY) ? 4 : 0;
+  return unsigned(mdbx_limits_keysize_min(table_flags));
 }
 
 unsigned actor_params::mdbx_keylen_max() const {
@@ -689,7 +701,7 @@ unsigned actor_params::mdbx_keylen_max() const {
 }
 
 unsigned actor_params::mdbx_datalen_min() const {
-  return (table_flags & MDBX_INTEGERDUP) ? 4 : 0;
+  return unsigned(mdbx_limits_valsize_min(table_flags));
 }
 
 unsigned actor_params::mdbx_datalen_max() const {

test/config.h++

@@ -25,6 +25,10 @@ enum actor_testcase {
   ac_hill,
   ac_deadread,
   ac_deadwrite,
+#if !defined(_WIN32) && !defined(_WIN64)
+  ac_forkread,
+  ac_forkwrite,
+#endif /* Windows */
   ac_jitter,
   ac_try,
   ac_copy,
@@ -59,7 +63,7 @@ const char *keygencase2str(const keygen_case);
 
 namespace config {
 
-enum scale_mode { no_scale, decimal, binary, duration };
+enum scale_mode { no_scale, decimal, binary, duration, intkey };
 
 bool parse_option(int argc, char *const argv[], int &narg, const char *option,
                   const char **value, const char *default_value = nullptr);
@@ -270,6 +274,7 @@ struct actor_params_pod {
   unsigned batch_read{0};
   unsigned batch_write{0};
 
+  unsigned prng_seed{0};
   unsigned delaystart{0};
   unsigned waitfor_nops{0};
   unsigned inject_writefaultn{0};

test/extra/doubtless_positioning.c++

@@ -0,0 +1,263 @@
+#include "mdbx.h++"
+#include <array>
+#include <functional>
+#include <iostream>
+#include <random>
+#include <unistd.h>
+
+static ::std::ostream &operator<<(::std::ostream &out,
+                                  const mdbx::cursor::move_operation op) {
+  static const char *const str[] = {"FIRST",
+                                    "FIRST_DUP",
+                                    "GET_BOTH",
+                                    "GET_BOTH_RANGE",
+                                    "GET_CURRENT",
+                                    "GET_MULTIPLE",
+                                    "LAST",
+                                    "LAST_DUP",
+                                    "NEXT",
+                                    "NEXT_DUP",
+                                    "NEXT_MULTIPLE",
+                                    "NEXT_NODUP",
+                                    "PREV",
+                                    "PREV_DUP",
+                                    "PREV_NODUP",
+                                    "SET",
+                                    "SET_KEY",
+                                    "SET_RANGE",
+                                    "PREV_MULTIPLE",
+                                    "SET_LOWERBOUND",
+                                    "SET_UPPERBOUND",
+                                    "TO_KEY_LESSER_THAN",
+                                    "TO_KEY_LESSER_OR_EQUAL",
+                                    "TO_KEY_EQUAL",
+                                    "TO_KEY_GREATER_OR_EQUAL",
+                                    "TO_KEY_GREATER_THAN",
+                                    "TO_EXACT_KEY_VALUE_LESSER_THAN",
+                                    "TO_EXACT_KEY_VALUE_LESSER_OR_EQUAL",
+                                    "TO_EXACT_KEY_VALUE_EQUAL",
+                                    "TO_EXACT_KEY_VALUE_GREATER_OR_EQUAL",
+                                    "TO_EXACT_KEY_VALUE_GREATER_THAN",
+                                    "TO_PAIR_LESSER_THAN",
+                                    "TO_PAIR_LESSER_OR_EQUAL",
+                                    "TO_PAIR_EQUAL",
+                                    "TO_PAIR_GREATER_OR_EQUAL",
+                                    "TO_PAIR_GREATER_THAN"};
+  return out << str[op];
+}
+
+using buffer = mdbx::default_buffer;
+using buffer_pair = mdbx::buffer_pair<buffer>;
+
+std::default_random_engine prng(42);
+
+static buffer random(const unsigned &value) {
+  switch (prng() % 3) {
+  default:
+    return buffer::hex(value);
+  case 1:
+    return buffer::base64(value);
+  case 2:
+    return buffer::base58(value);
+  }
+}
+
+static buffer random_key() { return random(prng() % 10007); }
+
+static buffer random_value() { return random(prng() % 47); }
+
+using predicate = std::function<bool(const mdbx::pair &, const mdbx::pair &)>;
+
+static bool probe(mdbx::txn txn, mdbx::map_handle dbi,
+                  mdbx::cursor::move_operation op, predicate cmp,
+                  const buffer_pair &pair) {
+  auto seeker = txn.open_cursor(dbi);
+  auto scanner = seeker.clone();
+
+  const bool scan_backward =
+      op == mdbx::cursor::key_lesser_than ||
+      op == mdbx::cursor::key_lesser_or_equal ||
+      op == mdbx::cursor::multi_exactkey_value_lesser_than ||
+      op == mdbx::cursor::multi_exactkey_value_lesser_or_equal ||
+      op == mdbx::cursor::pair_lesser_than ||
+      op == mdbx::cursor::pair_lesser_or_equal;
+
+  const bool is_multi = mdbx::is_multi(txn.get_handle_info(dbi).value_mode());
+
+  auto seek_result = seeker.move(op, pair.key, pair.value, false);
+  auto scan_result = scanner.fullscan(
+      [cmp, &pair](const mdbx::pair &scan) -> bool { return cmp(scan, pair); },
+      scan_backward);
+  if (seek_result.done == scan_result &&
+      (!scan_result ||
+       seeker.is_same_position(
+           scanner,
+           op < mdbx::cursor::multi_exactkey_value_lesser_than && is_multi)))
+    return true;
+
+  std::cerr << std::endl;
+  std::cerr << "bug:";
+  std::cerr << std::endl;
+  std::cerr << std::string(is_multi ? "multi" : "single") << "-map, op " << op
+            << ", key " << pair.key << ", value " << pair.value;
+  std::cerr << std::endl;
+  std::cerr << "\tscanner: ";
+  if (scan_result)
+    std::cerr << "     done, key " << scanner.current(false).key << ", value "
+              << scanner.current(false).value;
+  else
+    std::cerr << "not-found";
+  std::cerr << std::endl;
+  std::cerr << "\t seeker: " << (seek_result.done ? "     done" : "not-found")
+            << ", key " << seek_result.key << ", value " << seek_result.value;
+  std::cerr << std::endl;
+  return false;
+}
+
+static bool probe(mdbx::txn txn, mdbx::map_handle dbi,
+                  mdbx::cursor::move_operation op, predicate cmp) {
+  const auto pair = buffer_pair(random_key(), random_value());
+  const bool ok = probe(txn, dbi, op, cmp, pair);
+#if MDBX_DEBUG
+  if (!ok)
+    // повтор для отладки и поиска причин
+    probe(txn, dbi, op, cmp, pair);
+#endif /* MDBX_DEBUG */
+  return ok;
+}
+
+static bool test(mdbx::txn txn, mdbx::map_handle dbi) {
+  bool ok = true;
+
+  ok = probe(txn, dbi, mdbx::cursor::key_lesser_than,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               return mdbx_cmp(txn, dbi, l.key, r.key) < 0;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::key_lesser_or_equal,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               return mdbx_cmp(txn, dbi, l.key, r.key) <= 0;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::key_equal,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               return mdbx_cmp(txn, dbi, l.key, r.key) == 0;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::key_greater_or_equal,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               return mdbx_cmp(txn, dbi, l.key, r.key) >= 0;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::key_greater_than,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               return mdbx_cmp(txn, dbi, l.key, r.key) > 0;
+             }) &&
+       ok;
+
+  ok = probe(txn, dbi, mdbx::cursor::multi_exactkey_value_lesser_than,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               return mdbx_cmp(txn, dbi, l.key, r.key) == 0 &&
+                      mdbx_dcmp(txn, dbi, l.value, r.value) < 0;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::multi_exactkey_value_lesser_or_equal,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               return mdbx_cmp(txn, dbi, l.key, r.key) == 0 &&
+                      mdbx_dcmp(txn, dbi, l.value, r.value) <= 0;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::multi_exactkey_value_equal,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               return mdbx_cmp(txn, dbi, l.key, r.key) == 0 &&
+                      mdbx_dcmp(txn, dbi, l.value, r.value) == 0;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::multi_exactkey_value_greater_or_equal,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               return mdbx_cmp(txn, dbi, l.key, r.key) == 0 &&
+                      mdbx_dcmp(txn, dbi, l.value, r.value) >= 0;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::multi_exactkey_value_greater,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               return mdbx_cmp(txn, dbi, l.key, r.key) == 0 &&
+                      mdbx_dcmp(txn, dbi, l.value, r.value) > 0;
+             }) &&
+       ok;
+
+  ok = probe(txn, dbi, mdbx::cursor::pair_lesser_than,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               auto cmp = mdbx_cmp(txn, dbi, l.key, r.key);
+               if (cmp == 0)
+                 cmp = mdbx_dcmp(txn, dbi, l.value, r.value);
+               return cmp < 0;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::pair_lesser_or_equal,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               auto cmp = mdbx_cmp(txn, dbi, l.key, r.key);
+               if (cmp == 0)
+                 cmp = mdbx_dcmp(txn, dbi, l.value, r.value);
+               return cmp <= 0;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::pair_equal,
+             [](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               return l == r;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::pair_greater_or_equal,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               auto cmp = mdbx_cmp(txn, dbi, l.key, r.key);
+               if (cmp == 0)
+                 cmp = mdbx_dcmp(txn, dbi, l.value, r.value);
+               return cmp >= 0;
+             }) &&
+       ok;
+  ok = probe(txn, dbi, mdbx::cursor::pair_greater_than,
+             [txn, dbi](const mdbx::pair &l, const mdbx::pair &r) -> bool {
+               auto cmp = mdbx_cmp(txn, dbi, l.key, r.key);
+               if (cmp == 0)
+                 cmp = mdbx_dcmp(txn, dbi, l.value, r.value);
+               return cmp > 0;
+             }) &&
+       ok;
+  return ok;
+}
+
+int main(int argc, const char *argv[]) {
+  (void)argc;
+  (void)argv;
+
+  unlink("." MDBX_DATANAME);
+  unlink("." MDBX_LOCKNAME);
+  mdbx::env_managed env(".", mdbx::env_managed::create_parameters(),
+                        mdbx::env::operate_parameters(3));
+
+  auto txn = env.start_write();
+  auto single =
+      txn.create_map("single", mdbx::key_mode::usual, mdbx::value_mode::single);
+  auto multi =
+      txn.create_map("multi", mdbx::key_mode::usual, mdbx::value_mode::multi);
+  for (size_t i = 0; i < 1000; ++i) {
+    auto key = random_key();
+    txn.upsert(single, key, random_value());
+    for (auto n = prng() % 5 + 1; n > 0; --n)
+      txn.upsert(multi, key, random_value());
+  }
+  txn.commit_embark_read();
+
+  bool ok = true;
+  for (size_t i = 0; ok && i < 3333; ++i) {
+    ok = test(txn, single) && ok;
+    ok = test(txn, multi) && ok;
+  }
+
+  if (!ok) {
+    std::cerr << "Fail\n";
+    return EXIT_FAILURE;
+  }
+  std::cout << "OK\n";
+  return EXIT_SUCCESS;
+}

test/extra/hex_base64_base58.c++

@@ -0,0 +1,128 @@
+#include "mdbx.h++"
+#include <array>
+#include <iostream>
+#include <unistd.h>
+
+#include <functional>
+#include <random>
+
+using buffer = mdbx::default_buffer;
+
+std::default_random_engine prng(42);
+
+static buffer random(size_t length) {
+  buffer result(length);
+#if defined(__cpp_lib_span) && __cpp_lib_span >= 202002L
+  for (auto &i : result.bytes())
+    i = prng();
+#else
+  for (auto p = result.byte_ptr(); p < result.end_byte_ptr(); ++p)
+    *p = mdbx::byte(prng());
+#endif
+  return result;
+}
+
+static bool basic() {
+  bool ok = true;
+  const char *const hex_dump = "1D58fa\n2e46E3\nBd9c7A\nC0bF";
+  const uint8_t native[] = {0x1D, 0x58, 0xfa, 0x2e, 0x46, 0xE3,
+                            0xBd, 0x9c, 0x7A, 0xC0, 0xbF};
+
+  if (mdbx::slice(hex_dump).hex_decode(true) != mdbx::slice::wrap(native))
+    std::cerr << "hex_decode() failed\n";
+  else if (mdbx::slice::wrap(native).encode_hex(true, 4).hex_decode(true) !=
+           mdbx::slice::wrap(native))
+    std::cerr << "hex_encode(UPPERCASE) failed\n";
+  else if (mdbx::slice::wrap(native).encode_hex(false).hex_decode(true) !=
+           mdbx::slice::wrap(native))
+    std::cerr << "hex_encode(lowercase) failed\n";
+
+  if (mdbx::slice("").as_base64_string() != "" ||
+      mdbx::slice(" ").encode_base64().as_string() != "IA==" ||
+      mdbx::slice("~0").encode_base64().as_string() != "fjA=" ||
+      mdbx::slice("A_z").encode_base64().as_string() != "QV96" ||
+      mdbx::slice("Ka9q").encode_base64().as_string() != "S2E5cQ==" ||
+      mdbx::slice("123456789").encode_base64().as_string() != "MTIzNDU2Nzg5") {
+    std::cerr << "encode_base64() failed\n";
+    ok = false;
+  }
+
+  const uint8_t base58_rfc[] = {0x00, 0x00, 0x28, 0x7f, 0xb4, 0xcd};
+  if (mdbx::slice("").as_base58_string() != "" ||
+      mdbx::slice(" ").encode_base58().as_string() != "Z" ||
+      mdbx::slice("Hello World!").as_base58_string() != "2NEpo7TZRRrLZSi2U" ||
+      mdbx::slice("The quick brown fox jumps over the lazy dog.")
+              .encode_base58()
+              .as_string() !=
+          "USm3fpXnKG5EUBx2ndxBDMPVciP5hGey2Jh4NDv6gmeo1LkMeiKrLJUUBk6Z" ||
+      mdbx::slice::wrap(base58_rfc).as_base58_string() != "11233QC4" ||
+      mdbx::slice("~0").encode_base58().as_string() != "Aby" ||
+      mdbx::slice("A_z").encode_base58().as_string() != "NxZw" ||
+      mdbx::slice("Ka9q").encode_base58().as_string() != "2vkjDi" ||
+      mdbx::slice("123456789").encode_base58().as_string() != "dKYWwnRHc7Ck") {
+    std::cerr << "encode_base58() failed\n";
+    ok = false;
+  }
+
+  if (mdbx::slice("").base58_decode() != mdbx::slice() ||
+      mdbx::slice("Z").base58_decode() != mdbx::slice(" ") ||
+      mdbx::slice("2NEpo7TZRRrLZSi2U").base58_decode() != "Hello World!" ||
+      mdbx::slice(
+          "USm3fpXnKG5EUBx2ndxBDMPVciP5hGey2Jh4NDv6gmeo1LkMeiKrLJUUBk6Z")
+              .base58_decode() !=
+          mdbx::slice("The quick brown fox jumps over the lazy dog.") ||
+      mdbx::slice("11233QC4").base58_decode() !=
+          mdbx::slice::wrap(base58_rfc) ||
+      mdbx::slice("Aby").base58_decode() != mdbx::slice("~0") ||
+      mdbx::slice("NxZw").base58_decode() != mdbx::slice("A_z") ||
+      mdbx::slice("2vkjDi").base58_decode() != mdbx::slice("Ka9q") ||
+      mdbx::slice("dKYWwnRHc7Ck").base58_decode() != mdbx::slice("123456789")) {
+    std::cerr << "decode_base58() failed\n";
+    ok = false;
+  }
+
+  return ok;
+}
+
+int main(int argc, const char *argv[]) {
+  (void)argc;
+  (void)argv;
+
+  auto ok = basic();
+  for (size_t n = 0; n < 1000; ++n) {
+    for (size_t length = 0; ok && length < 111; ++length) {
+      const auto pattern = random(length);
+      if (pattern != pattern.encode_hex(bool(prng() & 1), prng() % 111)
+                         .hex_decode(true)
+                         .encode_hex()
+                         .hex_decode(false)) {
+        std::cerr << "hex encode/decode failed: n " << n << ", length "
+                  << length << std::endl;
+        ok = false;
+      }
+      if (pattern != pattern.encode_base64(unsigned(prng() % 111))
+                         .base64_decode(true)
+                         .encode_base64()
+                         .base64_decode(false)) {
+        std::cerr << "base64 encode/decode failed: n " << n << ", length "
+                  << length << std::endl;
+        ok = false;
+      }
+      if (pattern != pattern.encode_base58(unsigned(prng() % 111))
+                         .base58_decode(true)
+                         .encode_base58()
+                         .base58_decode(false)) {
+        std::cerr << "base58 encode/decode failed: n " << n << ", length "
+                  << length << std::endl;
+        ok = false;
+      }
+    }
+  }
+
+  if (!ok) {
+    std::cerr << "Fail\n";
+    return EXIT_FAILURE;
+  }
+  std::cout << "OK\n";
+  return EXIT_SUCCESS;
+}

test/extra/pcrf/pcrf_test.c

@@ -34,7 +34,7 @@
 
 #define IP_PRINTF_ARG_HOST(addr)                                               \
   (int)((addr) >> 24), (int)((addr) >> 16 & 0xff), (int)((addr) >> 8 & 0xff),  \
-      (int)((addr)&0xff)
+      (int)((addr) & 0xff)
 
 char opt_db_path[PATH_MAX] = "./mdbx_bench2";
 static MDBX_env *env;

test/fork.c++

@@ -0,0 +1,297 @@
+/*
+ * Copyright 2023 Leonid Yuriev <leo@yuriev.ru>
+ * and other libmdbx authors: please see AUTHORS file.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+
+#include "test.h++"
+
+#if !defined(_WIN32) && !defined(_WIN64)
+
+#include <sys/types.h>
+#include <sys/wait.h>
+
+class testcase_smoke4fork : public testcase {
+  using inherited = testcase;
+
+protected:
+  bool dbi_invalid{true};
+  bool dbi_stable{false};
+  unsigned dbi_state{0};
+
+public:
+  testcase_smoke4fork(const actor_config &config, const mdbx_pid_t pid)
+      : testcase(config, pid) {}
+  virtual void txn_end(bool abort) override;
+  bool run() override;
+  virtual bool smoke() = 0;
+  bool open_dbi();
+};
+
+bool testcase_smoke4fork::open_dbi() {
+  if (!dbi || dbi_invalid) {
+    if (dbi_stable ||
+        (mdbx_txn_flags(txn_guard.get()) & int(MDBX_TXN_RDONLY)) == 0) {
+      dbi = db_table_open(!dbi_stable);
+      dbi_invalid = false;
+    }
+  }
+
+  dbi_state = 0;
+  if (dbi && !dbi_invalid) {
+    unsigned unused_dbi_flags;
+    int err =
+        mdbx_dbi_flags_ex(txn_guard.get(), dbi, &unused_dbi_flags, &dbi_state);
+    if (unlikely(err != MDBX_SUCCESS))
+      failure_perror("mdbx_dbi_flags_ex()", err);
+    if ((dbi_state & (MDBX_DBI_CREAT | MDBX_DBI_FRESH)) == 0)
+      dbi_stable = true;
+  }
+  return !dbi_invalid;
+}
+
+void testcase_smoke4fork::txn_end(bool abort) {
+  if (dbi) {
+    if (abort) {
+      if (dbi_state & MDBX_DBI_CREAT)
+        dbi_stable = false;
+      if (dbi_state & MDBX_DBI_FRESH)
+        dbi_invalid = true;
+    } else {
+      if (dbi_state & (MDBX_DBI_CREAT | MDBX_DBI_FRESH))
+        dbi_stable = true;
+    }
+    dbi_state = 0;
+  }
+  inherited::txn_end(abort);
+}
+
+bool testcase_smoke4fork::run() {
+  static std::vector<pid_t> history;
+  const pid_t current_pid = getpid();
+  if (history.empty() || current_pid != history.front()) {
+    history.push_back(current_pid);
+    if (history.size() > /* TODO: add test option */ 2) {
+      log_notice("force exit to avoid fork-bomb: deep %zu, pid stack",
+                 history.size());
+      for (const auto pid : history)
+        logging::feed(" %d", pid);
+      logging::ln();
+      log_flush();
+      exit(0);
+    }
+  }
+  const int deep = (int)history.size();
+
+  int err = db_open__begin__table_create_open_clean(dbi);
+  if (unlikely(err != MDBX_SUCCESS)) {
+    log_notice("fork[deep %d, pid %d]: bailout-prepare due '%s'", deep,
+               current_pid, mdbx_strerror(err));
+    return false;
+  }
+  open_dbi();
+
+  if (flipcoin()) {
+    if (!smoke()) {
+      log_notice("%s[deep %d, pid %d] probe %s", "pre-fork", deep, current_pid,
+                 "failed");
+      return false;
+    }
+    log_verbose("%s[deep %d, pid %d] probe %s", "pre-fork", deep, current_pid,
+                "done");
+  } else {
+    log_verbose("%s[deep %d, pid %d] probe %s", "pre-fork", deep, current_pid,
+                "skipped");
+#ifdef __SANITIZE_ADDRESS__
+    const bool commit_txn_to_avoid_memleak = true;
+#else
+    const bool commit_txn_to_avoid_memleak = !RUNNING_ON_VALGRIND && flipcoin();
+#endif
+    if (commit_txn_to_avoid_memleak && txn_guard)
+      txn_end(false);
+  }
+
+  log_flush();
+  const pid_t child = fork();
+  if (child < 0)
+    failure_perror("fork()", errno);
+
+  if (child == 0) {
+    const pid_t new_pid = getpid();
+    log_verbose(">>> %s, deep %d, parent-pid %d, child-pid %d",
+                "mdbx_env_resurrect_after_fork()", deep, current_pid, new_pid);
+    log_flush();
+    int err = mdbx_env_resurrect_after_fork(db_guard.get());
+    log_verbose("<<< %s, deep %d, parent-pid %d, child-pid %d, err %d",
+                "mdbx_env_resurrect_after_fork()", deep, current_pid, new_pid,
+                err);
+    log_flush();
+    if (err != MDBX_SUCCESS)
+      failure_perror("mdbx_env_resurrect_after_fork()", err);
+    if (txn_guard) {
+      if (dbi_state & MDBX_DBI_CREAT)
+        dbi_invalid = true;
+      // if (dbi_state & MDBX_DBI_FRESH)
+      //   dbi_invalid = true;
+      dbi_state = 0;
+      mdbx_txn_abort(txn_guard.release());
+    }
+    if (!smoke()) {
+      log_notice("%s[deep %d, pid %d] probe %s", "fork-child", deep, new_pid,
+                 "failed");
+      return false;
+    }
+    log_verbose("%s[deep %d, pid %d] probe %s", "fork-child", deep, new_pid,
+                "done");
+    log_flush();
+    return true;
+  }
+
+  if (txn_guard)
+    txn_end(false);
+
+  int status = 0xdeadbeef;
+  if (waitpid(child, &status, 0) != child)
+    failure_perror("waitpid()", errno);
+
+  if (WIFEXITED(status)) {
+    const int code = WEXITSTATUS(status);
+    if (code != EXIT_SUCCESS) {
+      log_notice("%s[deep %d, pid %d] child-pid %d failed, err %d",
+                 "fork-child", deep, current_pid, child, code);
+      return false;
+    }
+    log_notice("%s[deep %d, pid %d] child-pid %d done", "fork-child", deep,
+               current_pid, child);
+  } else if (WIFSIGNALED(status)) {
+    const int sig = WTERMSIG(status);
+    switch (sig) {
+    case SIGABRT:
+    case SIGBUS:
+    case SIGFPE:
+    case SIGILL:
+    case SIGSEGV:
+      log_notice("%s[deep %d, pid %d] child-pid %d %s by SIG%s", "fork-child",
+                 deep, current_pid, child, "terminated", signal_name(sig));
+      break;
+    default:
+      log_notice("%s[deep %d, pid %d] child-id %d %s by SIG%s", "fork-child",
+                 deep, current_pid, child, "killed", signal_name(sig));
+    }
+    return false;
+  } else {
+    assert(false);
+  }
+
+  if (!smoke()) {
+    log_notice("%s[deep %d, pid %d] probe %s", "post-fork", deep, current_pid,
+               "failed");
+    return false;
+  }
+  log_verbose("%s[deep %d, pid %d] probe %s", "post-fork", deep, current_pid,
+              "done");
+  return true;
+}
+
+//-----------------------------------------------------------------------------
+
+class testcase_forkread : public testcase_smoke4fork {
+  using inherited = testcase_smoke4fork;
+
+public:
+  testcase_forkread(const actor_config &config, const mdbx_pid_t pid)
+      : testcase_smoke4fork(config, pid) {}
+  bool smoke() override;
+};
+REGISTER_TESTCASE(forkread);
+
+bool testcase_forkread::smoke() {
+  MDBX_envinfo env_info;
+  int err = mdbx_env_info_ex(db_guard.get(), txn_guard.get(), &env_info,
+                             sizeof(env_info));
+  if (err)
+    failure_perror("mdbx_env_info_ex()", err);
+
+  if (!txn_guard)
+    txn_begin(true);
+
+  MDBX_txn_info txn_info;
+  err = mdbx_txn_info(txn_guard.get(), &txn_info, sizeof(txn_info));
+  if (err)
+    failure_perror("mdbx_txn_info()", err);
+  fetch_canary();
+  err = mdbx_env_info_ex(db_guard.get(), txn_guard.get(), &env_info,
+                         sizeof(env_info));
+  if (err)
+    failure_perror("mdbx_env_info_ex()", err);
+
+  uint64_t seq;
+  if (dbi_invalid) {
+    err = mdbx_dbi_sequence(txn_guard.get(), dbi, &seq, 0);
+    if (unlikely(err != (dbi ? MDBX_BAD_DBI : MDBX_SUCCESS)))
+      failure("unexpected '%s' from mdbx_dbi_sequence(get, bad_dbi %d)",
+              mdbx_strerror(err), dbi);
+    open_dbi();
+  }
+  if (!dbi_invalid) {
+    err = mdbx_dbi_sequence(txn_guard.get(), dbi, &seq, 0);
+    if (unlikely(err != MDBX_SUCCESS))
+      failure("unexpected '%s' from mdbx_dbi_sequence(get, dbi %d)",
+              mdbx_strerror(err), dbi);
+  }
+  txn_end(false);
+  return true;
+}
+
+//-----------------------------------------------------------------------------
+
+class testcase_forkwrite : public testcase_forkread {
+  using inherited = testcase_forkread;
+
+public:
+  testcase_forkwrite(const actor_config &config, const mdbx_pid_t pid)
+      : testcase_forkread(config, pid) {}
+  bool smoke() override;
+};
+REGISTER_TESTCASE(forkwrite);
+
+bool testcase_forkwrite::smoke() {
+  const bool firstly_read = flipcoin();
+  if (firstly_read) {
+    if (!testcase_forkread::smoke())
+      return false;
+  }
+
+  if (!txn_guard)
+    txn_begin(false);
+
+  uint64_t seq;
+  if (dbi_invalid) {
+    int err = mdbx_dbi_sequence(txn_guard.get(), dbi, &seq, 0);
+    if (unlikely(err != (dbi ? MDBX_BAD_DBI : MDBX_EACCESS)))
+      failure("unexpected '%s' from mdbx_dbi_sequence(get, bad_dbi %d)",
+              mdbx_strerror(err), dbi);
+    open_dbi();
+  }
+  if (!dbi_invalid) {
+    int err = mdbx_dbi_sequence(txn_guard.get(), dbi, &seq, 1);
+    if (unlikely(err != MDBX_SUCCESS))
+      failure("unexpected '%s' from mdbx_dbi_sequence(inc, dbi %d)",
+              mdbx_strerror(err), dbi);
+  }
+  txn_end(false);
+
+  if (!firstly_read && !testcase_forkread::smoke())
+    return false;
+  return true;
+}
+
+#endif /* Windows */

test/hill.c++

@@ -52,7 +52,7 @@ bool testcase_hill::run() {
   speculum_committed.clear();
 
   /* TODO: работа в несколько потоков */
-  keyvalue_maker.setup(config.params, config.actor_id, 0 /* thread_number */);
+  keyvalue_maker.setup(config.params, 0 /* thread_number */);
 
   keygen::buffer a_key = keygen::alloc(config.params.keylen_max);
   keygen::buffer a_data_0 = keygen::alloc(config.params.datalen_max);
@@ -90,7 +90,7 @@ bool testcase_hill::run() {
     assert(b_serial > a_serial);
 
     // создаем первую запись из пары
-    const keygen::serial_t age_shift = UINT64_C(1) << (a_serial % 31);
+    const keygen::serial_t age_shift = keyvalue_maker.remix_age(a_serial);
     log_trace("uphill: insert-a (age %" PRIu64 ") %" PRIu64, age_shift,
               a_serial);
     generate_pair(a_serial, a_key, a_data_1, age_shift);
@@ -302,7 +302,7 @@ bool testcase_hill::run() {
     assert(b_serial > a_serial);
 
     // обновляем первую запись из пары
-    const keygen::serial_t age_shift = UINT64_C(1) << (a_serial % 31);
+    const keygen::serial_t age_shift = keyvalue_maker.remix_age(a_serial);
     log_trace("downhill: update-a (age 0->%" PRIu64 ") %" PRIu64, age_shift,
               a_serial);
     generate_pair(a_serial, a_key, a_data_0, 0);

test/jitter.c++

@@ -39,6 +39,12 @@ bool testcase_jitter::run() {
   if (upper_limit < 1)
     upper_limit = config.params.size_now * 2;
 
+  tablename_buf buffer;
+  const char *const tablename = db_tablename(buffer);
+  tablename_buf buffer_renamed;
+  const char *const tablename_renamed =
+      db_tablename(buffer_renamed, ".renamed");
+
   while (should_continue()) {
     jitter_delay();
     db_open();
@@ -48,6 +54,15 @@ bool testcase_jitter::run() {
       txn_begin(false);
       dbi = db_table_open(true);
       check_dbi_error(MDBX_SUCCESS, "created-uncommitted");
+
+      bool renamed = false;
+      if (flipcoin()) {
+        err = mdbx_dbi_rename(txn_guard.get(), dbi, tablename_renamed);
+        if (err != MDBX_SUCCESS)
+          failure_perror("jitter.rename-1", err);
+        renamed = true;
+      }
+
       // note: here and below the 4-byte length keys and value are used
       //       to be compatible with any Db-flags given from command line.
       MDBX_val k = {(void *)"k000", 4}, v = {(void *)"v001", 4};
@@ -75,7 +90,17 @@ bool testcase_jitter::run() {
         failure_perror("jitter.put-2", err);
       check_dbi_error(MDBX_BAD_DBI, "dropped-recreated-aborted");
       // restore DBI
-      dbi = db_table_open(false);
+      dbi = db_table_open(false, renamed);
+      if (renamed) {
+        err = mdbx_dbi_open(
+            txn_guard.get(), tablename_renamed,
+            flipcoin() ? MDBX_DB_ACCEDE : config.params.table_flags, &dbi);
+        if (unlikely(err != MDBX_SUCCESS))
+          failure_perror("open-renamed", err);
+        err = mdbx_dbi_rename(txn_guard.get(), dbi, tablename);
+        if (err != MDBX_SUCCESS)
+          failure_perror("jitter.rename-2", err);
+      }
       check_dbi_error(MDBX_SUCCESS, "dropped-recreated-aborted+reopened");
       v = {(void *)"v003", 4};
       err = mdbx_put(txn_guard.get(), dbi, &k, &v, MDBX_UPSERT);

test/keygen.c++

@@ -14,6 +14,39 @@
 
 #include "test.h++"
 
+static const uint64_t primes[64] = {
+    /* */
+    0, 1, 3, 7, 13, 31, 61, 127, 251, 509, 1021, 2039, 4093, 8191, 16381,
+    /* */
+    UINT64_C(32749), UINT64_C(65521), UINT64_C(131071), UINT64_C(262139),
+    UINT64_C(524287), UINT64_C(1048573), UINT64_C(2097143), UINT64_C(4194301),
+    UINT64_C(8388593), UINT64_C(16777213), UINT64_C(33554393),
+    UINT64_C(67108859), UINT64_C(134217689), UINT64_C(268435399),
+    UINT64_C(536870909), UINT64_C(1073741789), UINT64_C(2147483647),
+    UINT64_C(4294967291), UINT64_C(8589934583), UINT64_C(17179869143),
+    UINT64_C(34359738337), UINT64_C(68719476731), UINT64_C(137438953447),
+    UINT64_C(274877906899), UINT64_C(549755813881), UINT64_C(1099511627689),
+    UINT64_C(2199023255531), UINT64_C(4398046511093), UINT64_C(8796093022151),
+    UINT64_C(17592186044399), UINT64_C(35184372088777),
+    UINT64_C(70368744177643), UINT64_C(140737488355213),
+    UINT64_C(281474976710597), UINT64_C(562949953421231),
+    UINT64_C(1125899906842597), UINT64_C(2251799813685119),
+    UINT64_C(4503599627370449), UINT64_C(9007199254740881),
+    UINT64_C(18014398509481951), UINT64_C(36028797018963913),
+    UINT64_C(72057594037927931), UINT64_C(144115188075855859),
+    UINT64_C(288230376151711717), UINT64_C(576460752303423433),
+    UINT64_C(1152921504606846883), UINT64_C(2305843009213693951),
+    UINT64_C(4611686018427387847), UINT64_C(9223372036854775783)};
+
+/* static unsigned supid_log2(uint64_t v) {
+  unsigned r = 0;
+  while (v > 1) {
+    v >>= 1;
+    r += 1;
+  }
+  return r;
+} */
+
 namespace keygen {
 
 /* LY: https://en.wikipedia.org/wiki/Injective_function */
@@ -48,19 +81,19 @@ serial_t injective(const serial_t serial,
       10, 14, 22, 19, 3, 21, 18, 19, 26, 24, 2, 21, 25, 29, 24, 10, 11, 14, 20,
       19};
 
+  const auto mask = actor_params::serial_mask(bits);
   const auto mult = m[bits - 8];
   const auto shift = s[bits - 8];
   serial_t result = serial * mult;
   if (salt) {
     const unsigned left = bits / 2;
     const unsigned right = bits - left;
-    result = (result << left) |
+    result = (result << left) | ((result & mask) >> right);
-             ((result & actor_params::serial_mask(bits)) >> right);
     result = (result ^ salt) * mult;
   }
 
-  result ^= result << shift;
+  result ^= (result & mask) >> shift;
-  result &= actor_params::serial_mask(bits);
+  result &= mask;
   log_trace("keygen-injective: serial %" PRIu64 "/%u @%" PRIx64 ",%u,%" PRIu64
             " => %" PRIu64 "/%u",
             serial, bits, mult, shift, salt, result, bits);
@@ -79,7 +112,7 @@ void __hot maker::pair(serial_t serial, const buffer &key, buffer &value,
              unsigned(MDBX_INTEGERKEY | MDBX_REVERSEKEY | MDBX_DUPSORT))));
   assert(!(value_essentials.flags &
            ~(essentials::prng_fill_flag |
-             unsigned(MDBX_INTEGERDUP | MDBX_REVERSEDUP))));
+             unsigned(MDBX_INTEGERDUP | MDBX_REVERSEDUP | MDBX_DUPFIXED))));
 
   log_trace("keygen-pair: serial %" PRIu64 ", data-age %" PRIu64, serial,
             value_age);
@@ -111,7 +144,7 @@ void __hot maker::pair(serial_t serial, const buffer &key, buffer &value,
   }
 
   serial_t key_serial = serial;
-  serial_t value_serial = value_age << mapping.split;
+  serial_t value_serial = (value_age & value_age_mask) << mapping.split;
   if (mapping.split) {
     if (MDBX_db_flags_t(key_essentials.flags) & MDBX_DUPSORT) {
       key_serial >>= mapping.split;
@@ -126,15 +159,14 @@ void __hot maker::pair(serial_t serial, const buffer &key, buffer &value,
           actor_params::serial_mask(mapping.split);
     }
 
-    value_serial |= value_age << mapping.split;
     log_trace("keygen-pair: split@%u => k%" PRIu64 ", v%" PRIu64, mapping.split,
               key_serial, value_serial);
   }
 
   log_trace("keygen-pair: key %" PRIu64 ", value %" PRIu64, key_serial,
             value_serial);
-  mk_begin(key_serial, key_essentials, *key);
+  key_serial = mk_begin(key_serial, key_essentials, *key);
-  mk_begin(value_serial, value_essentials, *value);
+  value_serial = mk_begin(value_serial, value_essentials, *value);
 
 #if 0 /* unused for now */
   if (key->value.iov_len + value->value.iov_len > pair_maxlen) {
@@ -189,47 +221,82 @@ void __hot maker::pair(serial_t serial, const buffer &key, buffer &value,
   log_pair(logging::trace, "kv", key, value);
 }
 
-void maker::setup(const config::actor_params_pod &actor, unsigned actor_id,
+void maker::setup(const config::actor_params_pod &actor,
                   unsigned thread_number) {
 #if CONSTEXPR_ENUM_FLAGS_OPERATIONS
   static_assert(unsigned(MDBX_INTEGERKEY | MDBX_REVERSEKEY | MDBX_DUPSORT |
-                         MDBX_INTEGERDUP | MDBX_REVERSEDUP) < UINT16_MAX,
+                         MDBX_DUPFIXED | MDBX_INTEGERDUP | MDBX_REVERSEDUP) <
+                    UINT16_MAX,
                 "WTF?");
 #else
   assert(unsigned(MDBX_INTEGERKEY | MDBX_REVERSEKEY | MDBX_DUPSORT |
-                  MDBX_INTEGERDUP | MDBX_REVERSEDUP) < UINT16_MAX);
+                  MDBX_DUPFIXED | MDBX_INTEGERDUP | MDBX_REVERSEDUP) <
+         UINT16_MAX);
 #endif
+
   key_essentials.flags = uint16_t(
       actor.table_flags &
       MDBX_db_flags_t(MDBX_INTEGERKEY | MDBX_REVERSEKEY | MDBX_DUPSORT));
   assert(actor.keylen_min <= UINT16_MAX);
   key_essentials.minlen = uint16_t(actor.keylen_min);
   assert(actor.keylen_max <= UINT32_MAX);
-  key_essentials.maxlen =
+  key_essentials.maxlen = std::min(
-      std::min(uint32_t(actor.keylen_max),
+      uint32_t(actor.keylen_max),
-               uint32_t(mdbx_limits_keysize_max(
+      uint32_t(mdbx_limits_keysize_max(actor.pagesize, actor.table_flags)));
-                   actor.pagesize, MDBX_db_flags_t(key_essentials.flags))));
+  key_essentials.bits = (key_essentials.maxlen < sizeof(serial_t))
+                            ? key_essentials.maxlen * CHAR_BIT
+                            : sizeof(serial_t) * CHAR_BIT;
+  key_essentials.mask = actor_params::serial_mask(key_essentials.bits);
+  assert(key_essentials.bits > 63 ||
+         key_essentials.mask > primes[key_essentials.bits]);
 
   value_essentials.flags = uint16_t(
-      actor.table_flags & MDBX_db_flags_t(MDBX_INTEGERDUP | MDBX_REVERSEDUP));
+      actor.table_flags &
+      MDBX_db_flags_t(MDBX_INTEGERDUP | MDBX_REVERSEDUP | MDBX_DUPFIXED));
   assert(actor.datalen_min <= UINT16_MAX);
   value_essentials.minlen = uint16_t(actor.datalen_min);
   assert(actor.datalen_max <= UINT32_MAX);
-  value_essentials.maxlen =
+  value_essentials.maxlen = std::min(
-      std::min(uint32_t(actor.datalen_max),
+      uint32_t(actor.datalen_max),
-               uint32_t(mdbx_limits_valsize_max(
+      uint32_t(mdbx_limits_valsize_max(actor.pagesize, actor.table_flags)));
-                   actor.pagesize, MDBX_db_flags_t(key_essentials.flags))));
+  value_essentials.bits = (value_essentials.maxlen < sizeof(serial_t))
+                              ? value_essentials.maxlen * CHAR_BIT
+                              : sizeof(serial_t) * CHAR_BIT;
+  value_essentials.mask = actor_params::serial_mask(value_essentials.bits);
+  assert(value_essentials.bits > 63 ||
+         value_essentials.mask > primes[value_essentials.bits]);
 
   if (!actor.keygen.zero_fill) {
     key_essentials.flags |= essentials::prng_fill_flag;
     value_essentials.flags |= essentials::prng_fill_flag;
   }
 
-  (void)thread_number;
   mapping = actor.keygen;
-  salt =
+  const auto split = mapping.split;
-      (actor.keygen.seed + uint64_t(actor_id)) * UINT64_C(14653293970879851569);
+  while (mapping.split >
+             value_essentials.bits - essentials::value_age_minwidth ||
+         mapping.split >= mapping.width)
+    mapping.split -= 1;
+  if (split != mapping.width)
+    log_notice("keygen: reduce mapping-split from %u to %u", split,
+               mapping.split);
 
+  const auto width = mapping.width;
+  while (unsigned((actor.table_flags & MDBX_DUPSORT)
+                      ? mapping.width - mapping.split
+                      : mapping.width) > key_essentials.bits)
+    mapping.width -= 1;
+  if (width != mapping.width)
+    log_notice("keygen: reduce mapping-width from %u to %u", width,
+               mapping.width);
+
+  value_age_bits = value_essentials.bits - mapping.split;
+  value_age_mask = actor_params::serial_mask(value_age_bits);
+  assert(value_age_bits >= essentials::value_age_minwidth);
+
+  salt = (prng_state ^
+          (thread_number * 1575554837) * UINT64_C(59386707711075671)) *
+         UINT64_C(14653293970879851569);
   base = actor.serial_base();
 }
 
@@ -307,11 +374,24 @@ buffer alloc(size_t limit) {
   return buffer(ptr);
 }
 
-void __hot maker::mk_begin(const serial_t serial, const essentials &params,
+serial_t __hot maker::mk_begin(serial_t serial, const essentials &params,
-                           result &out) {
+                               result &out) {
   assert(out.limit >= params.maxlen);
   assert(params.maxlen >= params.minlen);
-  assert(params.maxlen >= length(serial));
+  assert(serial <= params.mask);
+  if (unlikely(serial > params.mask)) {
+#if 1
+    serial %= primes[params.bits];
+    assert(params.mask > primes[params.bits]);
+#else
+    const serial_t maxbits = params.maxlen * CHAR_BIT;
+    serial ^= (serial >> maxbits / 2) *
+              serial_t((sizeof(serial_t) > 4) ? UINT64_C(40719303417517073)
+                                              : UINT32_C(3708688457));
+    serial &= params.mask;
+#endif
+    assert(params.maxlen >= length(serial));
+  }
 
   out.value.iov_len = std::max(unsigned(params.minlen), length(serial));
   const auto variation = params.maxlen - params.minlen;
@@ -328,6 +408,7 @@ void __hot maker::mk_begin(const serial_t serial, const essentials &params,
   assert(length(serial) <= out.value.iov_len);
   assert(out.value.iov_len >= params.minlen);
   assert(out.value.iov_len <= params.maxlen);
+  return serial;
 }
 
 void __hot maker::mk_continue(const serial_t serial, const essentials &params,

test/keygen.h++

@@ -108,25 +108,24 @@ class maker {
 
   struct essentials {
     uint16_t minlen{0};
-    enum { prng_fill_flag = 1 };
+    enum { prng_fill_flag = 1, value_age_minwidth = 5 };
     uint16_t flags{0};
     uint32_t maxlen{0};
+    serial_t mask{0};
+    unsigned bits;
   } key_essentials, value_essentials;
+  unsigned value_age_bits;
+  serial_t value_age_mask{0};
 
-  static void mk_begin(const serial_t serial, const essentials &params,
+  static serial_t mk_begin(serial_t serial, const essentials &params,
-                       result &out);
+                           result &out);
   static void mk_continue(const serial_t serial, const essentials &params,
                           result &out);
-  static void mk(const serial_t serial, const essentials &params, result &out) {
-    mk_begin(serial, params, out);
-    mk_continue(serial, params, out);
-  }
 
 public:
   void pair(serial_t serial, const buffer &key, buffer &value,
             serial_t value_age, const bool keylen_changeable);
-  void setup(const config::actor_params_pod &actor, unsigned actor_id,
+  void setup(const config::actor_params_pod &actor, unsigned thread_number);
-             unsigned thread_number);
   bool is_unordered() const;
   void seek2end(serial_t &serial) const;
 
@@ -141,6 +140,11 @@ public:
     }
     return increment(serial, int64_t(uint64_t(delta) << mapping.split));
   }
+
+  serial_t remix_age(serial_t serial) const {
+    return (UINT64_C(768097847591) * (serial ^ UINT64_C(768097847591))) &
+           value_age_mask;
+  }
 };
 
 void log_pair(logging::loglevel level, const char *prefix, const buffer &key,

test/log.c++

@@ -53,10 +53,18 @@ static void mdbx_logger(MDBX_log_level_t priority, const char *function,
 
 namespace logging {
 
-static std::string prefix;
+/* логирование может быть вызвано после деструкторов */
-static std::string suffix;
+static char prefix_buf[64];
+static size_t prefix_len;
+static std::string suffix_buf;
+static const char *suffix_ptr = "~~~";
+struct suffix_cleaner {
+  suffix_cleaner() { suffix_ptr = ""; }
+  ~suffix_cleaner() { suffix_ptr = "~~~"; }
+} static anchor;
+
 static loglevel level;
-static FILE *last;
+static FILE *flow;
 
 void setlevel(loglevel priority) {
   level = priority;
@@ -67,12 +75,15 @@ void setlevel(loglevel priority) {
   log_trace("set mdbx debug-opts: 0x%02x", rc);
 }
 
-void setup(loglevel priority, const std::string &_prefix) {
+void setup(const std::string &prefix) {
-  setlevel(priority);
+  prefix_len = std::min(prefix.size(), sizeof(prefix_buf) - 1);
-  prefix = _prefix;
+  memcpy(prefix_buf, prefix.data(), prefix_len);
 }
 
-void setup(const std::string &_prefix) { prefix = _prefix; }
+void setup(loglevel priority, const std::string &prefix) {
+  setlevel(priority);
+  setup(prefix);
+}
 
 const char *level2str(const loglevel alevel) {
   switch (alevel) {
@@ -108,18 +119,18 @@ bool output(const loglevel priority, const char *format, ...) {
   return true;
 }
 
+void ln() {
+  if (flow) {
+    putc('\n', flow);
+    if (flow != stdout)
+      putc('\n', stdout);
+    flow = nullptr;
+  }
+}
+
 void output_nocheckloglevel_ap(const logging::loglevel priority,
                                const char *format, va_list ap) {
-  if (last) {
+  ln();
-    putc('\n', last);
-    fflush(last);
-    if (last == stderr) {
-      putc('\n', stdout);
-      fflush(stdout);
-    }
-    last = nullptr;
-  }
-
   chrono::time now = chrono::now_realtime();
   struct tm tm;
 #ifdef _MSC_VER
@@ -134,30 +145,27 @@ void output_nocheckloglevel_ap(const logging::loglevel priority,
   if (rc != MDBX_SUCCESS)
     failure_perror("localtime_r()", rc);
 
-  last = stdout;
+  fprintf(stdout,
-  fprintf(last,
           "[ %02d%02d%02d-%02d:%02d:%02d.%06d_%05lu %-10s %.4s ] %s" /* TODO */,
           tm.tm_year - 100, tm.tm_mon + 1, tm.tm_mday, tm.tm_hour, tm.tm_min,
           tm.tm_sec, chrono::fractional2us(now.fractional), (long)osal_getpid(),
-          prefix.c_str(), level2str(priority), suffix.c_str());
+          prefix_buf, level2str(priority), suffix_ptr);
 
   va_list ones;
   memset(&ones, 0, sizeof(ones)) /* zap MSVC and other goofy compilers */;
   if (same_or_higher(priority, error))
     va_copy(ones, ap);
-  vfprintf(last, format, ap);
+  vfprintf(stdout, format, ap);
 
   size_t len = strlen(format);
   char end = len ? format[len - 1] : '\0';
 
   switch (end) {
   default:
-    putc('\n', last);
+    putc('\n', stdout);
-    MDBX_CXX17_FALLTHROUGH; // fall through
+    break;
   case '\n':
-    fflush(last);
+    break;
-    last = nullptr;
-    MDBX_CXX17_FALLTHROUGH; // fall through
   case ' ':
   case '_':
   case ':':
@@ -167,46 +175,39 @@ void output_nocheckloglevel_ap(const logging::loglevel priority,
   case '\b':
   case '\r':
   case '\0':
+    flow = stdout;
     break;
   }
 
   if (same_or_higher(priority, error)) {
-    if (last != stderr) {
+    if (flow)
-      fprintf(stderr, "[ %05lu %-10s %.4s ] %s", (long)osal_getpid(),
+      flow = stderr;
-              prefix.c_str(), level2str(priority), suffix.c_str());
+    fprintf(stderr, "[ %05lu %-10s %.4s ] %s", (long)osal_getpid(), prefix_buf,
-      vfprintf(stderr, format, ones);
+            level2str(priority), suffix_ptr);
-      if (end == '\n')
+    vfprintf(stderr, format, ones);
-        fflush(stderr);
-      else
-        last = stderr;
-    }
     va_end(ones);
   }
 }
 
 bool feed_ap(const char *format, va_list ap) {
-  if (!last)
+  if (!flow)
     return false;
 
-  if (last == stderr) {
+  if (flow == stderr) {
     va_list ones;
     va_copy(ones, ap);
     vfprintf(stdout, format, ones);
     va_end(ones);
   }
-  vfprintf(last, format, ap);
+  vfprintf(flow, format, ap);
   size_t len = strlen(format);
-  if (len && format[len - 1] == '\n') {
+  if (len && format[len - 1] == '\n')
-    fflush(last);
+    flow = nullptr;
-    if (last == stderr)
-      fflush(stdout);
-    last = nullptr;
-  }
   return true;
 }
 
 bool feed(const char *format, ...) {
-  if (!last)
+  if (!flow)
     return false;
 
   va_list ap;
@@ -217,29 +218,36 @@ bool feed(const char *format, ...) {
 }
 
 local_suffix::local_suffix(const char *c_str)
-    : trim_pos(suffix.size()), indent(0) {
+    : trim_pos(suffix_buf.size()), indent(0) {
-  suffix.append(c_str);
+  suffix_buf.append(c_str);
+  suffix_ptr = suffix_buf.c_str();
 }
 
 local_suffix::local_suffix(const std::string &str)
-    : trim_pos(suffix.size()), indent(0) {
+    : trim_pos(suffix_buf.size()), indent(0) {
-  suffix.append(str);
+  suffix_buf.append(str);
+  suffix_ptr = suffix_buf.c_str();
 }
 
 void local_suffix::push() {
   indent += 1;
-  suffix.push_back('\t');
+  suffix_buf.push_back('\t');
+  suffix_ptr = suffix_buf.c_str();
 }
 
 void local_suffix::pop() {
   assert(indent > 0);
   if (indent > 0) {
     indent -= 1;
-    suffix.pop_back();
+    suffix_buf.pop_back();
+    suffix_ptr = suffix_buf.c_str();
   }
 }
 
-local_suffix::~local_suffix() { suffix.erase(trim_pos); }
+local_suffix::~local_suffix() {
+  suffix_buf.erase(trim_pos);
+  suffix_ptr = suffix_buf.c_str();
+}
 
 void progress_canary(bool active) {
   static chrono::time progress_timestamp;
@@ -294,73 +302,73 @@ void progress_canary(bool active) {
 } // namespace logging
 
 void log_extra(const char *msg, ...) {
+  logging::ln();
   if (logging::same_or_higher(logging::extra, logging::level)) {
     va_list ap;
     va_start(ap, msg);
     logging::output_nocheckloglevel_ap(logging::extra, msg, ap);
     va_end(ap);
-  } else
+  }
-    logging::last = nullptr;
 }
 
 void log_trace(const char *msg, ...) {
+  logging::ln();
   if (logging::same_or_higher(logging::trace, logging::level)) {
     va_list ap;
     va_start(ap, msg);
     logging::output_nocheckloglevel_ap(logging::trace, msg, ap);
     va_end(ap);
-  } else
+  }
-    logging::last = nullptr;
 }
 
 void log_debug(const char *msg, ...) {
+  logging::ln();
   if (logging::same_or_higher(logging::debug, logging::level)) {
     va_list ap;
     va_start(ap, msg);
     logging::output_nocheckloglevel_ap(logging::debug, msg, ap);
     va_end(ap);
-  } else
+  }
-    logging::last = nullptr;
 }
 
 void log_verbose(const char *msg, ...) {
+  logging::ln();
   if (logging::same_or_higher(logging::verbose, logging::level)) {
     va_list ap;
     va_start(ap, msg);
     logging::output_nocheckloglevel_ap(logging::verbose, msg, ap);
     va_end(ap);
-  } else
+  }
-    logging::last = nullptr;
 }
 
 void log_notice(const char *msg, ...) {
+  logging::ln();
   if (logging::same_or_higher(logging::notice, logging::level)) {
     va_list ap;
     va_start(ap, msg);
     logging::output_nocheckloglevel_ap(logging::notice, msg, ap);
     va_end(ap);
-  } else
+  }
-    logging::last = nullptr;
 }
 
 void log_warning(const char *msg, ...) {
+  logging::ln();
   if (logging::same_or_higher(logging::warning, logging::level)) {
     va_list ap;
     va_start(ap, msg);
     logging::output_nocheckloglevel_ap(logging::warning, msg, ap);
     va_end(ap);
-  } else
+  }
-    logging::last = nullptr;
 }
 
 void log_error(const char *msg, ...) {
+  logging::ln();
   if (logging::same_or_higher(logging::error, logging::level)) {
     va_list ap;
     va_start(ap, msg);
     logging::output_nocheckloglevel_ap(logging::error, msg, ap);
     va_end(ap);
-  } else
+  }
-    logging::last = nullptr;
 }
 
 void log_trouble(const char *where, const char *what, int errnum) {
@@ -371,4 +379,7 @@ bool log_enabled(const logging::loglevel priority) {
   return logging::same_or_higher(priority, logging::level);
 }
 
-void log_flush(void) { fflushall(); }
+void log_flush(void) {
+  logging::ln();
+  fflushall();
+}

test/log.h++

@@ -55,6 +55,7 @@ bool MDBX_PRINTF_ARGS(2, 3)
     output(const loglevel priority, const char *format, ...);
 bool feed_ap(const char *format, va_list ap);
 bool MDBX_PRINTF_ARGS(1, 2) feed(const char *format, ...);
+void ln();
 
 void inline MDBX_PRINTF_ARGS(2, 3)
     output_nocheckloglevel(const loglevel priority, const char *format, ...) {

test/long_stochastic.sh

@@ -13,6 +13,7 @@ DB_UPTO_MB=17408
 PAGESIZE=min
 DONT_CHECK_RAM=no
 EXTRA=no
+TAILLOG=0
 
 while [ -n "$1" ]
 do
@@ -35,9 +36,13 @@ do
     echo "--pagesize NN          Use specified page size (256 is minimal and used by default)"
     echo "--dont-check-ram-size  Don't check available RAM"
     echo "--extra                Iterate extra modes/flags"
+    echo "--taillog              Dump tail of test log on failure"
     echo "--help                 Print this usage help and exit"
     exit -2
   ;;
+  --taillog)
+    TAILLOG=3333
+  ;;
   --multi)
     LIST=basic
   ;;
@@ -62,7 +67,7 @@ do
     echo "       For instance, when the process 'A' explicitly marks a memory"
     echo "       region as 'undefined', the process 'B' fill it,"
     echo "       and after this process 'A' read such region, etc."
-    MONITOR="valgrind --trace-children=yes --log-file=valgrind-%p.log --leak-check=full --track-origins=yes --error-exitcode=42 --suppressions=test/valgrind_suppress.txt"
+    MONITOR="valgrind --trace-children=yes --log-file=valgrind-%p.log --leak-check=full --track-origins=yes --read-var-info=yes --error-exitcode=42 --suppressions=test/valgrind_suppress.txt"
     rm -f valgrind-*.log
   ;;
   --skip-make)
@@ -345,14 +350,38 @@ if which lz4 >/dev/null; then
   function logger {
     lz4 > ${TESTDB_DIR}/long.log.lz4
   }
+  function taillog {
+    if [ -s ${TESTDB_DIR}/long.log.lz4 ]; then
+      echo "=============================================== last ${TAILLOG} lines"
+      lz4 -d -c ${TESTDB_DIR}/long.log.lz4 | tail -n ${TAILLOG}
+    else
+      echo "=============================================== no test log"
+    fi
+  }
 elif which gzip >/dev/null; then
   function logger {
     gzip > ${TESTDB_DIR}/long.log.gz
   }
+  function taillog {
+    if [ -s ${TESTDB_DIR}/long.log.gz ]; then
+      echo "=============================================== last ${TAILLOG} lines"
+      gzip -d -c ${TESTDB_DIR}/long.log.gz | tail -n ${TAILLOG}
+    else
+      echo "=============================================== no test log"
+   fi
+  }
 else
   function logger {
     cat > ${TESTDB_DIR}/long.log
   }
+  function taillog {
+    if [ -s ${TESTDB_DIR}/long.log ]; then
+      echo "=============================================== last ${TAILLOG} lines"
+      tail -n ${TAILLOG} ${TESTDB_DIR}/long.log
+    else
+      echo "=============================================== no test log"
+    fi
+  }
 fi
 
 if [ "$EXTRA" != "no" ]; then
@@ -375,6 +404,9 @@ function bits2options {
 
 function failed {
   echo "FAILED" >&2
+  if [ ${TAILLOG} -gt 0 ]; then
+    taillog
+  fi
   exit 1
 }
 
@@ -421,120 +453,102 @@ for nops in 10 33 100 333 1000 3333 10000 33333 100000 333333 1000000 3333333 10
 
       split=30
       caption="Probe #$((++count)) int-key,with-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) int-key,int-data, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.integer --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.integer --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) with-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) int-key,fixdups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --keygen.seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=9 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=rnd \
         --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
       caption="Probe #$((++count)) fixdups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --keygen.seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=11 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=rnd \
         --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
 
       split=24
       caption="Probe #$((++count)) int-key,with-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) int-key,int-data, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.integer --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.integer --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) with-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) int-key,fixdups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --keygen.seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=10 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=rnd \
         --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
       caption="Probe #$((++count)) fixdups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --keygen.seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=12 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=rnd \
         --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
 
+
       split=16
       caption="Probe #$((++count)) int-key,w/o-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) int-key,with-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) int-key,int-data, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.integer --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.integer --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) w/o-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) with-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) int-key,fixdups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --keygen.seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=9 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=rnd \
         --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
       caption="Probe #$((++count)) fixdups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --keygen.seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=11 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=rnd \
         --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
 
       if [ "$EXTRA" != "no" ]; then
         split=10
         caption="Probe #$((++count)) int-key,w/o-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-          --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
+          --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
-          --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+          --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-          --keygen.seed=${seed}
         caption="Probe #$((++count)) int-key,with-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-          --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+          --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-          --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+          --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-          --keygen.seed=${seed}
         caption="Probe #$((++count)) int-key,int-data, split=${split}, case $((++subcase)) of ${cases}" probe \
-          --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.integer --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+          --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.integer --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-          --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+          --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-          --keygen.seed=${seed}
         caption="Probe #$((++count)) w/o-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-          --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
+          --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
-          --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+          --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-          --keygen.seed=${seed}
         caption="Probe #$((++count)) with-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-          --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+          --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-          --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+          --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-          --keygen.seed=${seed}
         caption="Probe #$((++count)) int-key,fixdups, split=${split}, case $((++subcase)) of ${cases}" probe \
-          --keygen.seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=13 \
+          --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=rnd \
           --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
         caption="Probe #$((++count)) fixdups, split=${split}, case $((++subcase)) of ${cases}" probe \
-          --keygen.seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=16 \
+          --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=rnd \
           --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
       fi
 
       split=4
       caption="Probe #$((++count)) int-key,w/o-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) int-key,int-data, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.integer --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.integer --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=max \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) w/o-dups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=-data.dups --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen.min=min --datalen.max=1111 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
-        --keygen.seed=${seed}
       caption="Probe #$((++count)) int-key,fixdups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --keygen.seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=21 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+key.integer,+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=rnd \
         --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
       caption="Probe #$((++count)) fixdups, split=${split}, case $((++subcase)) of ${cases}" probe \
-        --keygen.seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=32 \
+        --prng-seed=${seed} --pagesize=$PAGESIZE --size-upper-upto=${db_size_mb}M --table=+data.fixed --keygen.split=${split} --keylen.min=min --keylen.max=max --datalen=rnd \
         --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]}
     done # options
     loop=$((loop + 1))

test/main.c++

@@ -37,6 +37,7 @@ MDBX_NORETURN void usage(void) {
       "  --console[=yes/no]        Enable/disable console-like output\n"
       "  --cleanup-before[=YES/no] Cleanup/remove and re-create database\n"
       "  --cleanup-after[=YES/no]  Cleanup/remove database after completion\n"
+      "  --prng-seed=N             Seed PRNG\n"
       "Database size control:\n"
       "  --pagesize=...            Database page size: min, max, 256..65536\n"
       "  --size-lower=N[K|M|G|T]   Lower-bound of size in Kb/Mb/Gb/Tb\n"
@@ -60,6 +61,10 @@ MDBX_NORETURN void usage(void) {
       "  --append                      Append-mode insertions\n"
       "  --dead.reader                 Dead-reader simulator\n"
       "  --dead.writer                 Dead-writer simulator\n"
+#if !defined(_WIN32) && !defined(_WIN64)
+      "  --fork.reader                 After-fork reader\n"
+      "  --fork.writer                 After-fork writer\n"
+#endif /* Windows */
       "Actor options:\n"
       "  --batch.read=N                Read-operations batch size\n"
       "  --batch.write=N               Write-operations batch size\n"
@@ -84,7 +89,6 @@ MDBX_NORETURN void usage(void) {
       "  --datalen=N                   Set both min/max for data length\n"
       "  --keygen.width=N              TBD (see the source code)\n"
       "  --keygen.mesh=N               TBD (see the source code)\n"
-      "  --keygen.seed=N               TBD (see the source code)\n"
       "  --keygen.zerofill=yes|NO      TBD (see the source code)\n"
       "  --keygen.split=N              TBD (see the source code)\n"
       "  --keygen.rotate=N             TBD (see the source code)\n"
@@ -140,7 +144,7 @@ void actor_params::set_defaults(const std::string &tmpdir) {
   growth_step = -1;
   pagesize = -1;
 
-  keygen.seed = 1;
+  prng_seed = 0;
   keygen.zero_fill = false;
   keygen.keycase = kc_random;
   keygen.width = (table_flags & MDBX_DUPSORT) ? 32 : 64;
@@ -263,8 +267,19 @@ static void fixup4qemu(actor_params &params) {
   (void)params;
 }
 
-int main(int argc, char *const argv[]) {
+static void set_linebuf_append(FILE *out) {
+  setvbuf(out, NULL, _IOLBF, 65536);
+#if !defined(_WIN32) && !defined(_WIN64)
+  int fd = fileno(out);
+  int flags = fcntl(fd, F_GETFD);
+  if (flags != -1)
+    (void)fcntl(fd, F_SETFD, O_APPEND | flags);
+#endif /* !Windows */
+}
 
+int main(int argc, char *const argv[]) {
+  set_linebuf_append(stdout);
+  set_linebuf_append(stderr);
 #ifdef _DEBUG
   log_trace("#argc = %d", argc);
   for (int i = 0; i < argc; ++i)
@@ -434,9 +449,11 @@ int main(int argc, char *const argv[]) {
     if (config::parse_option(argc, argv, narg, "keygen.mesh",
                              params.keygen.mesh, 0, 64))
       continue;
-    if (config::parse_option(argc, argv, narg, "keygen.seed",
+    if (config::parse_option(argc, argv, narg, "prng-seed", params.prng_seed,
-                             params.keygen.seed, config::no_scale))
+                             config::no_scale)) {
+      prng_seed(params.prng_seed);
       continue;
+    }
     if (config::parse_option(argc, argv, narg, "keygen.zerofill",
                              params.keygen.zero_fill))
       continue;
@@ -453,49 +470,59 @@ int main(int argc, char *const argv[]) {
       keycase_setup(value, params);
       continue;
     }
-    if (config::parse_option(argc, argv, narg, "keylen.min", params.keylen_min,
+    if (config::parse_option(
-                             config::no_scale, params.mdbx_keylen_min(),
+            argc, argv, narg, "keylen.min", params.keylen_min,
-                             params.mdbx_keylen_max())) {
+            (params.table_flags & MDBX_INTEGERKEY) ? config::intkey
+                                                   : config::no_scale,
+            params.mdbx_keylen_min(), params.mdbx_keylen_max())) {
       if ((params.table_flags & MDBX_INTEGERKEY) ||
           params.keylen_max < params.keylen_min)
         params.keylen_max = params.keylen_min;
       continue;
     }
-    if (config::parse_option(argc, argv, narg, "keylen.max", params.keylen_max,
+    if (config::parse_option(
-                             config::no_scale, params.mdbx_keylen_min(),
+            argc, argv, narg, "keylen.max", params.keylen_max,
-                             params.mdbx_keylen_max())) {
+            (params.table_flags & MDBX_INTEGERKEY) ? config::intkey
+                                                   : config::no_scale,
+            params.mdbx_keylen_min(), params.mdbx_keylen_max())) {
       if ((params.table_flags & MDBX_INTEGERKEY) ||
           params.keylen_min > params.keylen_max)
         params.keylen_min = params.keylen_max;
       continue;
     }
-    if (config::parse_option(argc, argv, narg, "keylen", params.keylen_min,
+    if (config::parse_option(
-                             config::no_scale, params.mdbx_keylen_min(),
+            argc, argv, narg, "keylen", params.keylen_min,
-                             params.mdbx_keylen_max())) {
+            (params.table_flags & MDBX_INTEGERKEY) ? config::intkey
+                                                   : config::no_scale,
+            params.mdbx_keylen_min(), params.mdbx_keylen_max())) {
       params.keylen_max = params.keylen_min;
       continue;
     }
-    if (config::parse_option(argc, argv, narg, "datalen.min",
+    if (config::parse_option(
-                             params.datalen_min, config::no_scale,
+            argc, argv, narg, "datalen.min", params.datalen_min,
-                             params.mdbx_datalen_min(),
+            (params.table_flags & MDBX_INTEGERDUP) ? config::intkey
-                             params.mdbx_datalen_max())) {
+                                                   : config::no_scale,
+            params.mdbx_datalen_min(), params.mdbx_datalen_max())) {
       if ((params.table_flags & (MDBX_INTEGERDUP | MDBX_DUPFIXED)) ||
           params.datalen_max < params.datalen_min)
         params.datalen_max = params.datalen_min;
       continue;
     }
-    if (config::parse_option(argc, argv, narg, "datalen.max",
+    if (config::parse_option(
-                             params.datalen_max, config::no_scale,
+            argc, argv, narg, "datalen.max", params.datalen_max,
-                             params.mdbx_datalen_min(),
+            (params.table_flags & MDBX_INTEGERDUP) ? config::intkey
-                             params.mdbx_datalen_max())) {
+                                                   : config::no_scale,
+            params.mdbx_datalen_min(), params.mdbx_datalen_max())) {
       if ((params.table_flags & (MDBX_INTEGERDUP | MDBX_DUPFIXED)) ||
           params.datalen_min > params.datalen_max)
         params.datalen_min = params.datalen_max;
       continue;
     }
-    if (config::parse_option(argc, argv, narg, "datalen", params.datalen_min,
+    if (config::parse_option(
-                             config::no_scale, params.mdbx_datalen_min(),
+            argc, argv, narg, "datalen", params.datalen_min,
-                             params.mdbx_datalen_max())) {
+            (params.table_flags & MDBX_INTEGERDUP) ? config::intkey
+                                                   : config::no_scale,
+            params.mdbx_datalen_min(), params.mdbx_datalen_max())) {
       params.datalen_max = params.datalen_min;
       continue;
     }
@@ -591,6 +618,18 @@ int main(int argc, char *const argv[]) {
       configure_actor(last_space_id, ac_nested, value, params);
       continue;
     }
+#if !defined(_WIN32) && !defined(_WIN64)
+    if (config::parse_option(argc, argv, narg, "fork.reader", nullptr)) {
+      fixup4qemu(params);
+      configure_actor(last_space_id, ac_forkread, value, params);
+      continue;
+    }
+    if (config::parse_option(argc, argv, narg, "fork.writer", nullptr)) {
+      fixup4qemu(params);
+      configure_actor(last_space_id, ac_forkwrite, value, params);
+      continue;
+    }
+#endif /* Windows */
 
     if (*argv[narg] != '-') {
       fixup4qemu(params);
@@ -704,6 +743,14 @@ int main(int argc, char *const argv[]) {
     log_trace("=== done...");
   }
 
+  if (!failed) {
+    MDBX_envinfo info;
+    int err =
+        mdbx_preopen_snapinfo(params.pathname_db.c_str(), &info, sizeof(info));
+    if (err != MDBX_SUCCESS)
+      failure_perror("mdbx_preopen_snapinfo()", err);
+  }
+
   log_notice("RESULT: %s\n", failed ? "Failed" : "Successful");
   if (global::config::cleanup_after) {
     if (failed)

test/nested.c++

@@ -74,7 +74,7 @@ bool testcase_nested::setup() {
     return false;
   }
 
-  keyvalue_maker.setup(config.params, config.actor_id, 0 /* thread_number */);
+  keyvalue_maker.setup(config.params, 0 /* thread_number */);
   key = keygen::alloc(config.params.keylen_max);
   data = keygen::alloc(config.params.datalen_max);
   serial = 0;
@@ -292,8 +292,7 @@ retry:
 }
 
 bool testcase_nested::run() {
-  uint64_t seed =
+  uint64_t seed = prng64_map2_white(prng_state) + config.space_id;
-      prng64_map2_white(config.params.keygen.seed) + config.actor_id;
 
   clear_wholetable_passed = 0;
   clear_stepbystep_passed = 0;

test/osal-unix.c++

@@ -356,6 +356,7 @@ mdbx_pid_t osal_getpid(void) { return getpid(); }
 int osal_delay(unsigned seconds) { return sleep(seconds) ? errno : 0; }
 
 int osal_actor_start(const actor_config &config, mdbx_pid_t &pid) {
+  static sigset_t mask;
   if (children.empty()) {
     struct sigaction act;
     memset(&act, 0, sizeof(act));
@@ -366,7 +367,6 @@ int osal_actor_start(const actor_config &config, mdbx_pid_t &pid) {
     sigaction(SIGUSR1, &act, nullptr);
     sigaction(SIGUSR2, &act, nullptr);
 
-    sigset_t mask;
     sigemptyset(&mask);
     sigaddset(&mask, SIGCHLD);
     sigaddset(&mask, SIGUSR1);
@@ -377,6 +377,7 @@ int osal_actor_start(const actor_config &config, mdbx_pid_t &pid) {
   pid = fork();
 
   if (pid == 0) {
+    sigprocmask(SIG_BLOCK, &mask, nullptr);
     overlord_pid = getppid();
     const bool result = test_execute(config);
     exit(result ? EXIT_SUCCESS : EXIT_FAILURE);
@@ -400,7 +401,7 @@ void osal_killall_actors(void) {
   }
 }
 
-static const char *signal_name(const int sig) {
+const char *signal_name(const int sig) {
   if (sig == SIGHUP)
     return "HUP";
   if (sig == SIGINT)
@@ -532,24 +533,25 @@ int osal_actor_poll(mdbx_pid_t &pid, unsigned timeout) {
         children[pid] =
             (WEXITSTATUS(status) == EXIT_SUCCESS) ? as_successful : as_failed;
       else if (WIFSIGNALED(status)) {
+        int sig = WTERMSIG(status);
 #ifdef WCOREDUMP
         if (WCOREDUMP(status))
           children[pid] = as_coredump;
         else
 #endif /* WCOREDUMP */
-          switch (WTERMSIG(status)) {
+          switch (sig) {
           case SIGABRT:
           case SIGBUS:
           case SIGFPE:
           case SIGILL:
           case SIGSEGV:
-            log_notice("child pid %lu terminated by SIG%s", (long)pid,
+            log_notice("child pid %lu %s by SIG%s", (long)pid, "terminated",
-                       signal_name(WTERMSIG(status)));
+                       signal_name(sig));
             children[pid] = as_coredump;
             break;
           default:
-            log_notice("child pid %lu killed by SIG%s", (long)pid,
+            log_notice("child pid %lu %s by SIG%s", (long)pid, "killed",
-                       signal_name(WTERMSIG(status)));
+                       signal_name(sig));
             children[pid] = as_killed;
           }
       } else if (WIFSTOPPED(status))

test/osal.h++

@@ -46,3 +46,7 @@ std::string osal_tempdir(void);
 #define STDERR_FILENO _fileno(stderr)
 #endif
 #endif /* _MSC_VER */
+
+#if !defined(_WIN32) && !defined(_WIN64)
+const char *signal_name(const int sig);
+#endif /* Windows */

test/stochastic_small.sh

@@ -60,7 +60,7 @@ do
     echo "       For instance, when the process 'A' explicitly marks a memory"
     echo "       region as 'undefined', the process 'B' fill it,"
     echo "       and after this process 'A' read such region, etc."
-    MONITOR="valgrind --trace-children=yes --log-file=valgrind-%p.log --leak-check=full --track-origins=yes --error-exitcode=42 --suppressions=test/valgrind_suppress.txt"
+    MONITOR="valgrind --trace-children=yes --log-file=valgrind-%p.log --leak-check=full --track-origins=yes --read-var-info=yes --error-exitcode=42 --suppressions=test/valgrind_suppress.txt"
     rm -f valgrind-*.log
   ;;
   --skip-make)

test/test.c++

@@ -39,6 +39,12 @@ const char *testcase2str(const actor_testcase testcase) {
     return "ttl";
   case ac_nested:
     return "nested";
+#if !defined(_WIN32) && !defined(_WIN64)
+  case ac_forkread:
+    return "fork.reader";
+  case ac_forkwrite:
+    return "fork.writer";
+#endif /* Windows */
   }
 }
 
@@ -537,29 +543,43 @@ int testcase::db_open__begin__table_create_open_clean(MDBX_dbi &handle) {
   return err;
 }
 
-MDBX_dbi testcase::db_table_open(bool create) {
+const char *testcase::db_tablename(tablename_buf &buffer,
-  log_trace(">> testcase::db_table_create");
+                                   const char *suffix) const {
-
-  char tablename_buf[16];
   const char *tablename = nullptr;
   if (config.space_id) {
-    int rc = snprintf(tablename_buf, sizeof(tablename_buf), "TBL%04u",
+    int rc =
-                      config.space_id);
+        snprintf(buffer, sizeof(buffer), "TBL%04u%s", config.space_id, suffix);
     if (rc < 4 || rc >= (int)sizeof(tablename_buf) - 1)
       failure("snprintf(tablename): %d", rc);
-    tablename = tablename_buf;
+    tablename = buffer;
   }
   log_debug("use %s table", tablename ? tablename : "MAINDB");
+  return tablename;
+}
+
+MDBX_dbi testcase::db_table_open(bool create, bool expect_failure) {
+  log_trace(">> testcase::db_table_%s%s", create ? "create" : "open",
+            expect_failure ? "(expect_failure)" : "");
+
+  tablename_buf buffer;
+  const char *tablename = db_tablename(buffer);
 
   MDBX_dbi handle = 0;
-  int rc = mdbx_dbi_open(txn_guard.get(), tablename,
+  int rc = mdbx_dbi_open(
-                         (create ? MDBX_CREATE : MDBX_DB_DEFAULTS) |
+      txn_guard.get(), tablename,
-                             config.params.table_flags,
+      create ? (MDBX_CREATE | config.params.table_flags)
-                         &handle);
+             : (flipcoin() ? MDBX_DB_ACCEDE
-  if (unlikely(rc != MDBX_SUCCESS))
+                           : MDBX_DB_DEFAULTS | config.params.table_flags),
-    failure_perror("mdbx_dbi_open()", rc);
+      &handle);
+  if (unlikely(expect_failure != (rc != MDBX_SUCCESS))) {
+    char act[64];
+    snprintf(act, sizeof(act), "mdbx_dbi_open(create=%s,expect_failure=%s)",
+             create ? "true" : "false", expect_failure ? "true" : "false");
+    failure_perror(act, rc);
+  }
 
-  log_trace("<< testcase::db_table_create, handle %u", handle);
+  log_trace("<< testcase::db_table_%s%s, handle %u", create ? "create" : "open",
+            expect_failure ? "(expect_failure)" : "", handle);
   return handle;
 }
 
@@ -579,9 +599,9 @@ void testcase::db_table_drop(MDBX_dbi handle) {
 
 void testcase::db_table_clear(MDBX_dbi handle, MDBX_txn *txn) {
   log_trace(">> testcase::db_table_clear, handle %u", handle);
-  int rc = mdbx_drop(txn ? txn : txn_guard.get(), handle, false);
+  int err = mdbx_drop(txn ? txn : txn_guard.get(), handle, false);
-  if (unlikely(rc != MDBX_SUCCESS))
+  if (unlikely(err != MDBX_SUCCESS))
-    failure_perror("mdbx_drop(delete=false)", rc);
+    failure_perror("mdbx_drop(delete=false)", err);
   speculum.clear();
   log_trace("<< testcase::db_table_clear");
 }
@@ -589,21 +609,25 @@ void testcase::db_table_clear(MDBX_dbi handle, MDBX_txn *txn) {
 void testcase::db_table_close(MDBX_dbi handle) {
   log_trace(">> testcase::db_table_close, handle %u", handle);
   assert(!txn_guard);
-  int rc = mdbx_dbi_close(db_guard.get(), handle);
+  int err = mdbx_dbi_close(db_guard.get(), handle);
-  if (unlikely(rc != MDBX_SUCCESS))
+  if (unlikely(err != MDBX_SUCCESS))
-    failure_perror("mdbx_dbi_close()", rc);
+    failure_perror("mdbx_dbi_close()", err);
   log_trace("<< testcase::db_table_close");
 }
 
-void testcase::checkdata(const char *step, MDBX_dbi handle, MDBX_val key2check,
+bool testcase::checkdata(const char *step, MDBX_dbi handle, MDBX_val key2check,
                          MDBX_val expected_valued) {
   MDBX_val actual_value = expected_valued;
-  int rc = mdbx_get_equal_or_great(txn_guard.get(), handle, &key2check,
+  int err = mdbx_get_equal_or_great(txn_guard.get(), handle, &key2check,
-                                   &actual_value);
+                                    &actual_value);
-  if (unlikely(rc != MDBX_SUCCESS))
+  if (unlikely(err != MDBX_SUCCESS)) {
-    failure_perror(step, rc);
+    if (!config.params.speculum || err != MDBX_RESULT_TRUE)
+      failure_perror(step, (err == MDBX_RESULT_TRUE) ? MDBX_NOTFOUND : err);
+    return false;
+  }
   if (!is_samedata(&actual_value, &expected_valued))
     failure("%s data mismatch", step);
+  return true;
 }
 
 //-----------------------------------------------------------------------------
@@ -648,8 +672,8 @@ bool test_execute(const actor_config &config_const) {
                       size_t(config.params.nrepeat));
         else
           log_verbose("test successfully (iteration %zi)", iter);
-        config.params.keygen.seed += INT32_C(0xA4F4D37B);
+        prng_seed(config.params.prng_seed += INT32_C(0xA4F4D37B));
-        log_verbose("turn keygen to %u", config.params.keygen.seed);
+        log_verbose("turn PRNG to %u", config.params.prng_seed);
       }
 
     } while (config.params.nrepeat == 0 || iter < config.params.nrepeat);
@@ -968,7 +992,9 @@ int testcase::insert(const keygen::buffer &akey, const keygen::buffer &adata,
     }
 
     auto it_lowerbound = insertion_result.first;
-    if (++it_lowerbound != speculum.end()) {
+    if (insertion_result.second)
+      ++it_lowerbound;
+    if (it_lowerbound != speculum.end()) {
       const auto cursor_lowerbound = speculum_cursors[lowerbound].get();
       speculum_check_cursor("after-insert", "lowerbound", it_lowerbound,
                             cursor_lowerbound, MDBX_GET_CURRENT);
@@ -995,30 +1021,37 @@ int testcase::insert(const keygen::buffer &akey, const keygen::buffer &adata,
 
 int testcase::replace(const keygen::buffer &akey,
                       const keygen::buffer &new_data,
-                      const keygen::buffer &old_data, MDBX_put_flags_t flags) {
+                      const keygen::buffer &old_data, MDBX_put_flags_t flags,
+                      bool hush_keygen_mistakes) {
+  int expected_err = MDBX_SUCCESS;
   if (config.params.speculum) {
     const auto S_key = iov2dataview(akey);
     const auto S_old = iov2dataview(old_data);
     const auto S_new = iov2dataview(new_data);
     const auto removed = speculum.erase(SET::key_type(S_key, S_old));
-    if (unlikely(removed != 1)) {
+    if (unlikely(!removed)) {
       char dump_key[128], dump_value[128];
       log_error(
-          "speculum-%s: %s old value {%s, %s}", "replace",
+          "speculum-%s: no old pair {%s, %s} (keygen mistake)", "replace",
-          (removed > 1) ? "multi" : "no",
           mdbx_dump_val(&akey->value, dump_key, sizeof(dump_key)),
           mdbx_dump_val(&old_data->value, dump_value, sizeof(dump_value)));
-    }
+      expected_err = MDBX_NOTFOUND;
-    if (unlikely(!speculum.emplace(S_key, S_new).second)) {
+    } else if (unlikely(!speculum.emplace(S_key, S_new).second)) {
       char dump_key[128], dump_value[128];
       log_error(
-          "speculum-replace: new pair not inserted {%s, %s}",
+          "speculum-%s: %s {%s, %s}", "replace", "new pair not inserted",
           mdbx_dump_val(&akey->value, dump_key, sizeof(dump_key)),
           mdbx_dump_val(&new_data->value, dump_value, sizeof(dump_value)));
+      expected_err = MDBX_KEYEXIST;
     }
   }
-  return mdbx_replace(txn_guard.get(), dbi, &akey->value, &new_data->value,
+  int err = mdbx_replace(txn_guard.get(), dbi, &akey->value, &new_data->value,
-                      &old_data->value, flags);
+                         &old_data->value, flags);
+  if (err && err == expected_err && hush_keygen_mistakes) {
+    log_notice("speculum-%s: %s %d", "replace", "hust keygen mistake", err);
+    err = MDBX_SUCCESS;
+  }
+  return err;
 }
 
 int testcase::remove(const keygen::buffer &akey, const keygen::buffer &adata) {

test/test.h++

@@ -103,7 +103,7 @@ class registry {
   struct record {
     actor_testcase id = ac_none;
     std::string name;
-    bool (*review_params)(actor_params &) = nullptr;
+    bool (*review_params)(actor_params &, unsigned space_id) = nullptr;
     testcase *(*constructor)(const actor_config &, const mdbx_pid_t) = nullptr;
   };
   std::unordered_map<std::string, const record *> name2id;
@@ -124,8 +124,8 @@ public:
       add(this);
     }
   };
-  static bool review_actor_params(const actor_testcase id,
+  static bool review_actor_params(const actor_testcase id, actor_params &params,
-                                  actor_params &params);
+                                  const unsigned space_id);
   static testcase *create_actor(const actor_config &config,
                                 const mdbx_pid_t pid);
 };
@@ -232,7 +232,8 @@ protected:
   int insert(const keygen::buffer &akey, const keygen::buffer &adata,
              MDBX_put_flags_t flags);
   int replace(const keygen::buffer &akey, const keygen::buffer &new_value,
-              const keygen::buffer &old_value, MDBX_put_flags_t flags);
+              const keygen::buffer &old_value, MDBX_put_flags_t flags,
+              bool hush_keygen_mistakes = true);
   int remove(const keygen::buffer &akey, const keygen::buffer &adata);
 
   static int hsr_callback(const MDBX_env *env, const MDBX_txn *txn,
@@ -248,9 +249,10 @@ protected:
   void db_prepare();
   void db_open();
   void db_close();
-  void txn_begin(bool readonly, MDBX_txn_flags_t flags = MDBX_TXN_READWRITE);
+  virtual void txn_begin(bool readonly,
+                         MDBX_txn_flags_t flags = MDBX_TXN_READWRITE);
   int breakable_commit();
-  void txn_end(bool abort);
+  virtual void txn_end(bool abort);
   int breakable_restart();
   void txn_restart(bool abort, bool readonly,
                    MDBX_txn_flags_t flags = MDBX_TXN_READWRITE);
@@ -261,11 +263,14 @@ protected:
   void txn_inject_writefault(MDBX_txn *txn);
   void fetch_canary();
   void update_canary(uint64_t increment);
-  void checkdata(const char *step, MDBX_dbi handle, MDBX_val key2check,
+  bool checkdata(const char *step, MDBX_dbi handle, MDBX_val key2check,
                  MDBX_val expected_valued);
   unsigned txn_underutilization_x256(MDBX_txn *txn) const;
 
-  MDBX_dbi db_table_open(bool create);
+  using tablename_buf = char[32];
+  const char *db_tablename(tablename_buf &buffer,
+                           const char *suffix = "") const;
+  MDBX_dbi db_table_open(bool create, bool expect_failure = false);
   void db_table_drop(MDBX_dbi handle);
   void db_table_clear(MDBX_dbi handle, MDBX_txn *txn = nullptr);
   void db_table_close(MDBX_dbi handle);
@@ -298,8 +303,9 @@ public:
     memset(&last, 0, sizeof(last));
   }
 
-  static bool review_params(actor_params &params) {
+  static bool review_params(actor_params &params, unsigned space_id) {
     // silently fix key/data length for fixed-length modes
+    params.prng_seed += bleach32(space_id);
     if ((params.table_flags & MDBX_INTEGERKEY) &&
         params.keylen_min != params.keylen_max)
       params.keylen_min = params.keylen_max;

test/ttl.c++

@@ -119,9 +119,8 @@ bool testcase_ttl::run() {
     return false;
   }
 
-  uint64_t seed =
+  uint64_t seed = prng64_map2_white(prng_state) + config.space_id;
-      prng64_map2_white(config.params.keygen.seed) + config.actor_id;
+  keyvalue_maker.setup(config.params, 0 /* thread_number */);
-  keyvalue_maker.setup(config.params, config.actor_id, 0 /* thread_number */);
   key = keygen::alloc(config.params.keylen_max);
   data = keygen::alloc(config.params.datalen_max);
   const MDBX_put_flags_t insert_flags =

test/utils.c++

@@ -107,18 +107,22 @@ uint64_t prng64_white(uint64_t &state) {
   return bleach64(state);
 }
 
-uint32_t prng32(uint64_t &state) {
+uint32_t prng32_fast(uint64_t &state) {
-  return (uint32_t)(prng64_careless(state) >> 32);
+  return uint32_t(prng64_careless(state) >> 32);
+}
+
+uint32_t prng32_white(uint64_t &state) {
+  return bleach32(uint32_t(prng64_careless(state) >> 32));
 }
 
 void prng_fill(uint64_t &state, void *ptr, size_t bytes) {
-  uint32_t u32 = prng32(state);
+  uint32_t u32 = prng32_fast(state);
 
   while (bytes >= 4) {
     memcpy(ptr, &u32, 4);
     ptr = (uint32_t *)ptr + 1;
     bytes -= 4;
-    u32 = prng32(state);
+    u32 = prng32_fast(state);
   }
 
   switch (bytes & 3) {
@@ -136,11 +140,11 @@ void prng_fill(uint64_t &state, void *ptr, size_t bytes) {
   }
 }
 
-static __thread uint64_t prng_state;
+/* __thread */ uint64_t prng_state;
 
 void prng_seed(uint64_t seed) { prng_state = bleach64(seed); }
 
-uint32_t prng32(void) { return prng32(prng_state); }
+uint32_t prng32(void) { return prng32_white(prng_state); }
 
 uint64_t prng64(void) { return prng64_white(prng_state); }
 

test/utils.h++

@@ -288,24 +288,26 @@ inline bool is_samedata(const MDBX_val &a, const MDBX_val &b) {
 }
 std::string format(const char *fmt, ...);
 
-static inline uint64_t bleach64(uint64_t v) {
+static inline uint64_t bleach64(uint64_t x) {
-  // Tommy Ettinger, https://www.blogger.com/profile/04953541827437796598
+  // NASAM from Tommy Ettinger,
-  // http://mostlymangling.blogspot.com/2019/01/better-stronger-mixer-and-test-procedure.html
+  // https://www.blogger.com/profile/04953541827437796598
-  v ^= rot64(v, 25) ^ rot64(v, 50);
+  // http://mostlymangling.blogspot.com/2020/01/nasam-not-another-strange-acronym-mixer.html
-  v *= UINT64_C(0xA24BAED4963EE407);
+  x ^= rot64(x, 25) ^ rot64(x, 47);
-  v ^= rot64(v, 24) ^ rot64(v, 49);
+  x *= UINT64_C(0x9E6C63D0676A9A99);
-  v *= UINT64_C(0x9FB21C651E98DF25);
+  x ^= x >> 23 ^ x >> 51;
-  return v ^ v >> 28;
+  x *= UINT64_C(0x9E6D62D06F6A9A9B);
+  x ^= x >> 23 ^ x >> 51;
+  return x;
 }
 
 static inline uint32_t bleach32(uint32_t x) {
   // https://github.com/skeeto/hash-prospector
-  // exact bias: 0.17353355999581582
+  // exact bias: 0.10760229515479501
   x ^= x >> 16;
-  x *= UINT32_C(0x7feb352d);
+  x *= UINT32_C(0x21f0aaad);
   x ^= 0x3027C563 ^ (x >> 15);
-  x *= UINT32_C(0x846ca68b);
+  x *= UINT32_C(0x0d35a2d97);
-  x ^= x >> 16;
+  x ^= x >> 15;
   return x;
 }
 
@@ -343,9 +345,11 @@ static inline double u64_to_double1(uint64_t v) {
 }
 
 uint64_t prng64_white(uint64_t &state);
-uint32_t prng32(uint64_t &state);
+uint32_t prng32_white(uint64_t &state);
+uint32_t prng32_fast(uint64_t &state);
 void prng_fill(uint64_t &state, void *ptr, size_t bytes);
 
+extern uint64_t prng_state;
 void prng_seed(uint64_t seed);
 uint32_t prng32(void);
 uint64_t prng64(void);

test/valgrind_suppress.txt

@@ -2,7 +2,6 @@
    msync-whole-mmap-1
    Memcheck:Param
    msync(start)
-   fun:msync
    ...
    fun:sync_locked*
 }
@@ -10,7 +9,6 @@
    msync-whole-mmap-2
    Memcheck:Param
    msync(start)
-   fun:msync
    ...
    fun:env_sync*
 }
@@ -18,7 +16,6 @@
    msync-whole-mmap-3
    Memcheck:Param
    msync(start)
-   fun:msync
    ...
    fun:map_resize*
 }
@@ -26,7 +23,6 @@
    msync-wipe-steady
    Memcheck:Param
    msync(start)
-   fun:msync
    ...
    fun:wipe_steady*
 }
@@ -34,7 +30,6 @@
    msync-meta
    Memcheck:Param
    msync(start)
-   fun:msync
    ...
    fun:meta_sync*
 }
@@ -42,7 +37,6 @@
    msync-spill
    Memcheck:Param
    msync(start)
-   fun:msync
    ...
    fun:txn_spill*
 }
@@ -72,7 +66,6 @@
    pwrite-page-flush
    Memcheck:Param
    pwrite(buf)
-   fun:pwrite
    ...
    fun:iov_write*
 }
@@ -80,7 +73,6 @@
    pwrite64-page-flush
    Memcheck:Param
    pwrite64(buf)
-   fun:pwrite
    ...
    fun:iov_write*
 }
@@ -90,16 +82,14 @@
 #   pwritev-page-flush
 #   Memcheck:Param
 #   pwritev(vector[...])
-#   fun:pwritev
 #   ...
 #   fun:iov_write*
 #}
-# for((i=0;i<64;++i)); do echo -e "{\n   pwritev-page-flush-$i\n   Memcheck:Param\n   pwritev(vector[$i])\n   fun:pwritev\n   ...\n   fun:iov_write*\n}"; done >> valgrind_suppress.txt
+# for((i=0;i<64;++i)); do echo -e "{\n   pwritev-page-flush-$i\n   Memcheck:Param\n   pwritev(vector[$i])\n   ...\n   fun:iov_write*\n}"; done >> valgrind_suppress.txt
 {
    pwritev-page-flush-0
    Memcheck:Param
    pwritev(vector[0])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -107,7 +97,6 @@
    pwritev-page-flush-1
    Memcheck:Param
    pwritev(vector[1])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -115,7 +104,6 @@
    pwritev-page-flush-2
    Memcheck:Param
    pwritev(vector[2])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -123,7 +111,6 @@
    pwritev-page-flush-3
    Memcheck:Param
    pwritev(vector[3])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -131,7 +118,6 @@
    pwritev-page-flush-4
    Memcheck:Param
    pwritev(vector[4])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -139,7 +125,6 @@
    pwritev-page-flush-5
    Memcheck:Param
    pwritev(vector[5])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -147,7 +132,6 @@
    pwritev-page-flush-6
    Memcheck:Param
    pwritev(vector[6])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -155,7 +139,6 @@
    pwritev-page-flush-7
    Memcheck:Param
    pwritev(vector[7])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -163,7 +146,6 @@
    pwritev-page-flush-8
    Memcheck:Param
    pwritev(vector[8])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -171,7 +153,6 @@
    pwritev-page-flush-9
    Memcheck:Param
    pwritev(vector[9])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -179,7 +160,6 @@
    pwritev-page-flush-10
    Memcheck:Param
    pwritev(vector[10])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -187,7 +167,6 @@
    pwritev-page-flush-11
    Memcheck:Param
    pwritev(vector[11])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -195,7 +174,6 @@
    pwritev-page-flush-12
    Memcheck:Param
    pwritev(vector[12])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -203,7 +181,6 @@
    pwritev-page-flush-13
    Memcheck:Param
    pwritev(vector[13])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -211,7 +188,6 @@
    pwritev-page-flush-14
    Memcheck:Param
    pwritev(vector[14])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -219,7 +195,6 @@
    pwritev-page-flush-15
    Memcheck:Param
    pwritev(vector[15])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -227,7 +202,6 @@
    pwritev-page-flush-16
    Memcheck:Param
    pwritev(vector[16])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -235,7 +209,6 @@
    pwritev-page-flush-17
    Memcheck:Param
    pwritev(vector[17])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -243,7 +216,6 @@
    pwritev-page-flush-18
    Memcheck:Param
    pwritev(vector[18])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -251,7 +223,6 @@
    pwritev-page-flush-19
    Memcheck:Param
    pwritev(vector[19])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -259,7 +230,6 @@
    pwritev-page-flush-20
    Memcheck:Param
    pwritev(vector[20])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -267,7 +237,6 @@
    pwritev-page-flush-21
    Memcheck:Param
    pwritev(vector[21])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -275,7 +244,6 @@
    pwritev-page-flush-22
    Memcheck:Param
    pwritev(vector[22])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -283,7 +251,6 @@
    pwritev-page-flush-23
    Memcheck:Param
    pwritev(vector[23])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -291,7 +258,6 @@
    pwritev-page-flush-24
    Memcheck:Param
    pwritev(vector[24])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -299,7 +265,6 @@
    pwritev-page-flush-25
    Memcheck:Param
    pwritev(vector[25])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -307,7 +272,6 @@
    pwritev-page-flush-26
    Memcheck:Param
    pwritev(vector[26])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -315,7 +279,6 @@
    pwritev-page-flush-27
    Memcheck:Param
    pwritev(vector[27])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -323,7 +286,6 @@
    pwritev-page-flush-28
    Memcheck:Param
    pwritev(vector[28])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -331,7 +293,6 @@
    pwritev-page-flush-29
    Memcheck:Param
    pwritev(vector[29])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -339,7 +300,6 @@
    pwritev-page-flush-30
    Memcheck:Param
    pwritev(vector[30])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -347,7 +307,6 @@
    pwritev-page-flush-31
    Memcheck:Param
    pwritev(vector[31])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -355,7 +314,6 @@
    pwritev-page-flush-32
    Memcheck:Param
    pwritev(vector[32])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -363,7 +321,6 @@
    pwritev-page-flush-33
    Memcheck:Param
    pwritev(vector[33])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -371,7 +328,6 @@
    pwritev-page-flush-34
    Memcheck:Param
    pwritev(vector[34])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -379,7 +335,6 @@
    pwritev-page-flush-35
    Memcheck:Param
    pwritev(vector[35])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -387,7 +342,6 @@
    pwritev-page-flush-36
    Memcheck:Param
    pwritev(vector[36])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -395,7 +349,6 @@
    pwritev-page-flush-37
    Memcheck:Param
    pwritev(vector[37])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -403,7 +356,6 @@
    pwritev-page-flush-38
    Memcheck:Param
    pwritev(vector[38])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -411,7 +363,6 @@
    pwritev-page-flush-39
    Memcheck:Param
    pwritev(vector[39])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -419,7 +370,6 @@
    pwritev-page-flush-40
    Memcheck:Param
    pwritev(vector[40])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -427,7 +377,6 @@
    pwritev-page-flush-41
    Memcheck:Param
    pwritev(vector[41])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -435,7 +384,6 @@
    pwritev-page-flush-42
    Memcheck:Param
    pwritev(vector[42])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -443,7 +391,6 @@
    pwritev-page-flush-43
    Memcheck:Param
    pwritev(vector[43])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -451,7 +398,6 @@
    pwritev-page-flush-44
    Memcheck:Param
    pwritev(vector[44])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -459,7 +405,6 @@
    pwritev-page-flush-45
    Memcheck:Param
    pwritev(vector[45])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -467,7 +412,6 @@
    pwritev-page-flush-46
    Memcheck:Param
    pwritev(vector[46])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -475,7 +419,6 @@
    pwritev-page-flush-47
    Memcheck:Param
    pwritev(vector[47])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -483,7 +426,6 @@
    pwritev-page-flush-48
    Memcheck:Param
    pwritev(vector[48])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -491,7 +433,6 @@
    pwritev-page-flush-49
    Memcheck:Param
    pwritev(vector[49])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -499,7 +440,6 @@
    pwritev-page-flush-50
    Memcheck:Param
    pwritev(vector[50])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -507,7 +447,6 @@
    pwritev-page-flush-51
    Memcheck:Param
    pwritev(vector[51])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -515,7 +454,6 @@
    pwritev-page-flush-52
    Memcheck:Param
    pwritev(vector[52])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -523,7 +461,6 @@
    pwritev-page-flush-53
    Memcheck:Param
    pwritev(vector[53])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -531,7 +468,6 @@
    pwritev-page-flush-54
    Memcheck:Param
    pwritev(vector[54])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -539,7 +475,6 @@
    pwritev-page-flush-55
    Memcheck:Param
    pwritev(vector[55])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -547,7 +482,6 @@
    pwritev-page-flush-56
    Memcheck:Param
    pwritev(vector[56])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -555,7 +489,6 @@
    pwritev-page-flush-57
    Memcheck:Param
    pwritev(vector[57])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -563,7 +496,6 @@
    pwritev-page-flush-58
    Memcheck:Param
    pwritev(vector[58])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -571,7 +503,6 @@
    pwritev-page-flush-59
    Memcheck:Param
    pwritev(vector[59])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -579,7 +510,6 @@
    pwritev-page-flush-60
    Memcheck:Param
    pwritev(vector[60])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -587,7 +517,6 @@
    pwritev-page-flush-61
    Memcheck:Param
    pwritev(vector[61])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -595,7 +524,6 @@
    pwritev-page-flush-62
    Memcheck:Param
    pwritev(vector[62])
-   fun:pwritev
    ...
    fun:iov_write*
 }
@@ -603,7 +531,6 @@
    pwritev-page-flush-63
    Memcheck:Param
    pwritev(vector[63])
-   fun:pwritev
    ...
    fun:iov_write*
 }