mdbx: выпуск 0.12.4 "Арта-333"

Стабилизирующий выпуск с исправлением обнаруженных ошибок, устранением недочетов и технических долгов. Ветка 0.12 считается готовой к продуктовому использованию, получает статус стабильной и далее будет получать только исправление ошибок. Разработка будет продолжена в ветке 0.13, а ветка 0.11 становится архивной. Благодарности: -------------- - Max <maxc0d3r@protonmail.com> за сообщение о проблеме ERROR_SHARING_VIOLATION в режиме MDBX_EXCLUSIVE на Windows. - Alisher Ashyrov <https://t.me/a1is43ras4> за сообщение о проблеме с assert-проверкой и содействие в отладке. - Masatoshi Fukunaga <https://gitflic.ru/user/mah0x211> за сообщение о проблеме `put(MDBX_UPSERT+MDBX_ALLDUPS)` для случая замены всех значений в subDb. Исправления (без корректировок новых функций): ---------------------------------------------- - Устранен регресс после коммита 474391c83c, приводящий к возврату ERROR_SHARING_VIOLATION в Windows при открытии БД в режиме MDBX_EXCLUSIVE для чтения-записи. - Добавлено ограничение размера отображения при коротком read-only файле, для предотвращения ошибки ERROR_NOT_ENOUGH_MEMORY в Windows, которая возникает в этом случае и совсем не информативна для пользователя. - Произведен рефакторинг `dxb_resize()`, в том числе, для устранения срабатывания assert-проверки `size_bytes == env->me_dxb_mmap.current` в специфических многопоточных сценариях использования. Проверка срабатывала только в отладочных сборках, при специфическом наложении во времени читающей и пишущей транзакции в разных потоках, одновременно с изменением размера БД. Кроме срабатывание проверки, каких-либо других последствий не возникало. - Устранена проблема в `put(MDBX_UPSERT+MDBX_ALLDUPS)` для случая замены всех значений единственного ключа в subDb. В ходе этой операции subDb становится полностью пустой, без каких-либо страниц и именно эта ситуация не была учтена в коде, что приводило к повреждению БД при фиксации такой транзакции. - Устранена излишняя assert-проверка внутри `override_meta()`. Что в отладочных сборках могло приводить к ложным срабатываниям при восстановлении БД, в том числе при автоматическом откате слабых мета-страниц. - Скорректированы макросы `__cold`/`__hot`, в том числе для устранения проблемы `error: inlining failed in call to ‘always_inline FOO(...)’: target specific option mismatch` при сборке посредством GCC >10.x для SH4. Ликвидация технических долгов и мелочи: --------------------------------------- - Исправлены многочисленные опечатки в документации. - Доработан тест для полной стохастической проверки `MDBX_EKEYMISMATCH` в режиме `MDBX_APPEND`. - Расширены сценарии запуска `mdbx_chk` из CMake-тестов для проверки как в обычном, так и эксклюзивном режимах чтения-записи. - Уточнены спецификаторы `const` и `noexcept` для нескольких методов в C++ API. - Устранено использование стека под буферы для `wchar`-преобразования путей. - Для Windows добавлена функция `mdbx_env_get_path()` для получения пути к БД в формате многобайтных символов. - Добавлены doxygen-описания для API с широкими символами. - Устранены предупреждения статического анализатора MSVC, все они были несущественные, либо ложные. - Устранено ложное предупреждение GCC при сборке для SH4. - Добавлена поддержка ASAN (Address Sanitizer) при сборке посредством MSVC. - Расширен набор перебираемых режимов в скрипте `test/long_stochastic.sh`, добавлена опция `--extra`. - В C++ API добавлена поддержка расширенных опций времени выполнения `mdbx::extra_runtime_option`, аналогично `enum MDBX_option_t` из C API. - Вывод всех счетчиков page-operations в `mdbx_stat`. 63 files changed, 1161 insertions(+), 569 deletions(-) Signed-off-by: Леонид Юрьев (Leonid Yuriev) <leo@yuriev.ru>
mdbx-tools: вывод всех счетчиков page-operations в mdbx_stat.
2025-12-15 04:32:21 +08:00 · 2023-03-03 23:23:08 +03:00 · 2023-03-03 21:18:35 +03:00 · 2023-03-02 16:34:19 +03:00 · 2023-03-01 23:22:50 +03:00 · 2023-03-01 01:09:10 +03:00
68 changed files with 5613 additions and 3441 deletions
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
 ##
-##  Copyright 2020-2022 Leonid Yuriev <leo@yuriev.ru>
+##  Copyright 2020-2023 Leonid Yuriev <leo@yuriev.ru>
 ##  and other libmdbx authors: please see AUTHORS file.
 ##  All rights reserved.
 ##
--- a/2
+++ b/2
@@ -1,4 +1,4 @@
-Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>.
+Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>.
 Copyright 2011-2015 Howard Chu, Symas Corp.
 Copyright 2015,2016 Peter-Service R&D LLC.
 All rights reserved.
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -4,6 +4,228 @@ 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).

+## v0.12.4 (Арта-333) от 2023-03-03
+
+Стабилизирующий выпуск с исправлением обнаруженных ошибок, устранением
+недочетов и технических долгов. Ветка 0.12 считается готовой к
+продуктовому использованию, получает статус стабильной и далее будет
+получать только исправление ошибок. Разработка будет продолжена в ветке
+0.13, а ветка 0.11 становится архивной.
+
+```
+63 files changed, 1161 insertions(+), 569 deletions(-)
+Signed-off-by: Леонид Юрьев (Leonid Yuriev) <leo@yuriev.ru>
+```
+
+Благодарности:
+
+ - Max <maxc0d3r@protonmail.com> за сообщение о проблеме ERROR_SHARING_VIOLATION
+   в режиме MDBX_EXCLUSIVE на Windows.
+ - Alisher Ashyrov <https://t.me/a1is43ras4> за сообщение о проблеме
+   с assert-проверкой и содействие в отладке.
+ - Masatoshi Fukunaga <https://gitflic.ru/user/mah0x211> за сообщение о проблеме
+   `put(MDBX_UPSERT+MDBX_ALLDUPS)` для случая замены всех значений в subDb.
+
+Исправления (без корректировок новых функций):
+
+ - Устранен регресс после коммита 474391c83c5f81def6fdf3b0b6f5716a87b78fbf,
+   приводящий к возврату ERROR_SHARING_VIOLATION в Windows при открытии БД
+   в режиме MDBX_EXCLUSIVE для чтения-записи.
+
+ - Добавлено ограничение размера отображения при коротком read-only файле, для
+   предотвращения ошибки ERROR_NOT_ENOUGH_MEMORY в Windows, которая возникает
+   в этом случае и совсем не информативна для пользователя.
+
+ - Произведен рефакторинг `dxb_resize()`, в том числе, для устранения срабатывания
+   assert-проверки `size_bytes == env->me_dxb_mmap.current` в специфических
+   многопоточных сценариях использования. Проверка срабатывала только в
+   отладочных сборках, при специфическом наложении во времени читающей и
+   пишущей транзакции в разных потоках, одновременно с изменением размера БД.
+   Кроме срабатывание проверки, каких-либо других последствий не возникало.
+
+ - Устранена проблема в `put(MDBX_UPSERT+MDBX_ALLDUPS)` для случая замены
+   всех значений единственного ключа в subDb. В ходе этой операции subDb
+   становится полностью пустой, без каких-либо страниц и именно эта
+   ситуация не была учтена в коде, что приводило к повреждению БД
+   при фиксации такой транзакции.
+
+ - Устранена излишняя assert-проверка внутри `override_meta()`.
+   Что в отладочных сборках могло приводить к ложным срабатываниям
+   при восстановлении БД, в том числе при автоматическом откате слабых
+   мета-страниц.
+
+ - Скорректированы макросы `__cold`/`__hot`, в том числе для устранения проблемы
+   `error: inlining failed in call to ‘always_inline FOO(...)’: target specific option mismatch`
+   при сборке посредством GCC >10.x для SH4.
+
+Ликвидация технических долгов и мелочи:
+
+ - Исправлены многочисленные опечатки в документации.
+ - Доработан тест для полной стохастической проверки `MDBX_EKEYMISMATCH` в режиме `MDBX_APPEND`.
+ - Расширены сценарии запуска `mdbx_chk` из CMake-тестов для проверки как в обычном,
+   так и эксклюзивном режимах чтения-записи.
+ - Уточнены спецификаторы `const` и `noexcept` для нескольких методов в C++ API.
+ - Устранено использование стека под буферы для `wchar`-преобразования путей.
+ - Для Windows добавлена функция `mdbx_env_get_path()` для получения пути к БД
+   в формате многобайтных символов.
+ - Добавлены doxygen-описания для API с широкими символами.
+ - Устранены предупреждения статического анализатора MSVC,
+   все они были несущественные, либо ложные.
+ - Устранено ложное предупреждение GCC при сборке для SH4.
+ - Добавлена поддержка ASAN (Address Sanitizer) при сборке посредством MSVC.
+ - Расширен набор перебираемых режимов в скрипте `test/long_stochastic.sh`,
+   добавлена опция `--extra`.
+ - В C++ API добавлена поддержка расширенных опций времени выполнения `mdbx::extra_runtime_option`,
+   аналогично `enum MDBX_option_t` из C API.
+ - Вывод всех счетчиков page-operations в `mdbx_stat`.
+
+
+-------------------------------------------------------------------------------
+
+
+## v0.12.3 (Акула) от 2023-01-07
+
+Выпуск с существенными доработками и новой функциональностью в память о закрытом open-source
+[проекте "Акула"](https://erigon.substack.com/p/winding-down-support-for-akula-project).
+
+Добавлена prefault-запись, переделан контроль “некогерентности” unified page/buffer cache, изменена тактика слияния страниц и т.д.
+Стало ещё быстрее, в некоторых сценариях вдвое.
+
+```
+20 files changed, 4508 insertions(+), 2928 deletions(-)
+Signed-off-by: Леонид Юрьев (Leonid Yuriev) <leo@yuriev.ru>
+```
+
+Благодарности:
+
+ - [Alex Sharov](https://t.me/AskAlexSharov) и команде [Erigon](https://github.com/ledgerwatch/erigon) за тестирование.
+ - [Simon Leier](https://t.me/leisim) за сообщение о сбоях и тестирование.
+
+Новое:
+
+ - Использование адреса [https://libmdbx.dqdkfa.ru/dead-github](https://libmdbx.dqdkfa.ru/dead-github)
+   для отсылки к сохранённым в web.archive.org копиям ресурсов, уничтоженных администрацией Github.
+
+ - Реализована prefault-запись при выделении страниц для read-write отображений.
+   Это приводит к кратному снижению системных издержек и существенному увеличению
+   производительности в соответствующих сценариях использования, когда:
+    - размер БД и объём данных существенно больше ОЗУ;
+    - используется режим `MDBX_WRITEMAP`;
+    - не-мелкие транзакции (по ходу транзакции выделяется многие сотни или тысячи страниц).
+
+   В режиме `MDBX_WRITEMAP` выделение/переиспользование страниц приводит
+   к page-fault и чтению страницы с диска, даже если содержимое страницы
+   не нужно (будет перезаписано). Это является следствием работы подсистемы
+   виртуальной памяти, а штатный способ лечения через `MADV_REMOVE`
+   работает не на всех ФС и обычно дороже получаемой экономии.
+
+   Теперь в libmdbx используется "упреждающая запись" таких страниц,
+   которая на системах с [unified page cache](https://www.opennet.ru/base/dev/ubc.txt.html)
+   приводит к "вталкиванию" данных, устраняя необходимость чтения с диска при
+   обращении к такой странице памяти.
+
+   Новый функционал работает в согласованности с автоматическим управлением read-ahead
+   и кэшем статуса присутствия страниц в ОЗУ, посредством [mincore()](https://man7.org/linux/man-pages/man2/mincore.2.html).
+
+ - Добавлена опция `MDBX_opt_prefault_write_enable` для возможности принудительного
+   включения/выключения prefault-записи.
+
+ - Реализован динамический выбор между сквозной записью на диск и обычной записью
+   с последующим [fdatasync()](https://man7.org/linux/man-pages/man3/fdatasync.3p.html)
+   управляемый опцией `MDBX_opt_writethrough_threshold`.
+
+   В долговечных (durable) режимах данные на диск могут быть сброшены двумя способами:
+     - сквозной записью через файловый дескриптор открытый с `O_DSYNC`;
+     - обычной записью с последующим вызовом `fdatasync()`.
+
+   Первый способ выгоднее при записи малого количества страниц и/или если
+   канал взаимодействия с диском/носителем имеет близкую к нулю задержку.
+   Второй способ выгоднее если требуется записать много страниц и/или канал
+   взаимодействия имеет весомую задержку (датацентры, облака). Добавленная
+   опция `MDBX_opt_writethrough_threshold` позволяет во время выполнения
+   задать порог для динамического выбора способа записи в зависимости от
+   объема и конкретных условия использования.
+
+ - Автоматическая установка `MDBX_opt_rp_augment_limit` в зависимости от размера БД.
+
+ - Запрещение разного режима `MDBX_WRITEMAP` между процессами в режимах
+   с отложенной/ленивой записью, так как в этом случае невозможно
+   обеспечить сброс данных на диск во всех случаях на всех поддерживаемых платформах.
+
+ - Добавлена опция сборки `MDBX_MMAP_USE_MS_ASYNC` позволяющая отключить
+   использование системного вызова `msync(MS_ASYNC)`, в использовании
+   которого нет необходимости на подавляющем большинстве актуальных ОС.
+   По-умолчанию `MDBX_MMAP_USE_MS_ASYNC=0` (выключено) на Linux и других
+   системах с unified page cache. Такое поведение (без использования
+   `msync(MS_ASYNC)`) соответствует неизменяемой (hardcoded) логике LMDB. В
+   результате, в простых/наивных бенчмарках, libmdbx опережает LMDB
+   примерно также как при реальном применении.
+
+   На всякий случай стоит еще раз отметить/напомнить, что на Windows
+   предположительно libmdbx будет отставать от LMDB в сценариях с
+   множеством мелких транзакций, так как libmdbx осознанно использует на
+   Windows файловые блокировки, которые медленные (плохо реализованы в ядре
+   ОС), но позволяют застраховать пользователей от массы неверных действий
+   приводящих к повреждению БД.
+
+ - Поддержка не-печатных имен для subDb.
+
+ - Добавлен явный выбор `tls_model("local-dynamic")` для обхода проблемы
+   `relocation R_X86_64_TPOFF32 against FOO cannot be used with -shared`
+   из-за ошибки в CLANG приводящей к использованию неверного режима `ls_model`.
+
+ - Изменение тактики слияния страниц при удалении.
+   Теперь слияние выполняется преимущественно с уже измененной/грязной страницей.
+   Если же справа и слева обе страницы с одинаковым статусом,
+   то с наименее заполненной, как прежде. В сценариях с массивным удалением
+   это позволяет увеличить производительность до 50%.
+
+ - Добавлен контроль отсутствия LCK-файлов с альтернативным именованием.
+
+Исправления (без корректировок новых функций):
+
+ - Изменение размера отображения если это требуется для сброса данных на
+   диск при вызове `mdbx_env_sync()` из параллельного потока выполнения вне
+   работающей транзакции.
+
+ - Исправление регресса после коммита db72763de049d6e4546f838277fe83b9081ad1de от 2022-10-08
+   в логике возврата грязных страниц в режиме `MDBX_WRITEMAP`, из-за чего
+   освободившиеся страницы использовались не немедленно, а попадали в
+   retired-список совершаемой транзакции и происходил необоснованный рост
+   размера транзакции.
+
+ - Устранение SIGSEGV или ошибочного вызова `free()` в ситуациях
+   повторного открытия среды посредством `mdbx_env_open()`.
+
+ - Устранение ошибки совершенной в коммите fe20de136c22ed3bc4c6d3f673e79c106e824f60 от 2022-09-18,
+   в результате чего на Linux в режиме `MDBX_WRITEMAP` никогда не вызывался `msync()`.
+   Проблема существует только в релизе 0.12.2.
+
+ - Добавление подсчета грязных страниц в `MDBX_WRITEMAP` для предоставления посредством `mdbx_txn_info()`
+   актуальной информации об объеме изменений в процессе транзакций чтения-записи.
+
+ - Исправление несущественной опечатки в условиях `#if` определения порядка байт.
+
+ - Исправление сборки для случая `MDBX_PNL_ASCENDING=1`.
+
+Ликвидация технических долгов и мелочи:
+
+ - Доработка поддержки авто-слияния записей GC внутри `page_alloc_slowpath()`.
+ - Устранение несущественных предупреждений Coverity.
+ - Использование единого курсора для поиска в GC.
+ - Переработка внутренних флагов связанных с выделением страниц из GC.
+ - Доработка подготовки резерва перед обновлением GC при включенном BigFoot.
+ - Оптимизация `pnl_merge()` для случаев неперекрывающихся объединяемых списков.
+ - Оптимизация поддержки отсортированного списка страниц в `dpl_append()`.
+ - Ускорение работы `mdbx_chk` при обработке пользовательских записей в `@MAIN`.
+ - Переработка LRU-отметок для спиллинга.
+ - Переработка контроля "некогерентности" Unified page cache для уменьшения накладных расходов.
+ - Рефакторинг и микрооптимизация.
+
+
+-------------------------------------------------------------------------------
+
+
 ## v0.12.2 (Иван Ярыгин) от 2022-11-11

 Выпуск с существенными доработками и новой функциональностью
@@ -471,7 +693,7 @@ Minors:

 The stable release with the complete workaround for an incoherence flaw of Linux unified page/buffer cache.
 Nonetheless the cause for this trouble may be an issue of Intel CPU cache/MESI.
-See [issue#269](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/269) for more information.
+See [issue#269](https://libmdbx.dqdkfa.ru/dead-github/issues/269) for more information.

 Acknowledgements:

@@ -480,8 +702,8 @@ Acknowledgements:

 Fixes:

- - [Added complete workaround](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/269) for an incoherence flaw of Linux unified page/buffer cache.
- - [Fixed](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/272) cursor reusing for read-only transactions.
+ - [Added complete workaround](https://libmdbx.dqdkfa.ru/dead-github/issues/269) for an incoherence flaw of Linux unified page/buffer cache.
+ - [Fixed](https://libmdbx.dqdkfa.ru/dead-github/issues/272) cursor reusing for read-only transactions.
 - Fixed copy&paste typo inside `mdbx::cursor::find_multivalue()`.

 Minors:
@@ -496,7 +718,7 @@ Minors:
 ## v0.11.5 at 2022-02-23

 The release with the temporary hotfix for a flaw of Linux unified page/buffer cache.
-See [issue#269](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/269) for more information.
+See [issue#269](https://libmdbx.dqdkfa.ru/dead-github/issues/269) for more information.

 Acknowledgements:

@@ -506,10 +728,10 @@ Acknowledgements:

 Fixes:

- - [Added hotfix](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/269) for a flaw of Linux unified page/buffer cache.
- - [Fixed/Reworked](https://web.archive.org/web/https://github.com/erthink/libmdbx/pull/270) move-assignment operators for "managed" classes of C++ API.
+ - [Added hotfix](https://libmdbx.dqdkfa.ru/dead-github/issues/269) for a flaw of Linux unified page/buffer cache.
+ - [Fixed/Reworked](https://libmdbx.dqdkfa.ru/dead-github/pull/270) move-assignment operators for "managed" classes of C++ API.
 - Fixed potential `SIGSEGV` while open DB with overrided non-default page size.
- - [Made](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/267) `mdbx_env_open()` idempotence in failure cases.
+ - [Made](https://libmdbx.dqdkfa.ru/dead-github/issues/267) `mdbx_env_open()` idempotence in failure cases.
 - Refined/Fixed pages reservation inside `mdbx_update_gc()` to avoid non-reclamation in a rare cases.
 - Fixed typo in a retained space calculation for the hsr-callback.

@@ -542,15 +764,15 @@ New features, extensions and improvements:
 Fixes:

 - Fixed handling `MDBX_opt_rp_augment_limit` for GC's records from huge transactions (Erigon/Akula/Ethereum).
- - [Fixed](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/258) build on Android (avoid including `sys/sem.h`).
- - [Fixed](https://web.archive.org/web/https://github.com/erthink/libmdbx/pull/261) missing copy assignment operator for `mdbx::move_result`.
+ - [Fixed](https://libmdbx.dqdkfa.ru/dead-github/issues/258) build on Android (avoid including `sys/sem.h`).
+ - [Fixed](https://libmdbx.dqdkfa.ru/dead-github/pull/261) missing copy assignment operator for `mdbx::move_result`.
 - Fixed missing `&` for `std::ostream &operator<<()` overloads.
 - Fixed unexpected `EXDEV` (Cross-device link) error from `mdbx_env_copy()`.
 - Fixed base64 encoding/decoding bugs in auxillary C++ API.
 - Fixed overflow of `pgno_t` during checking PNL on 64-bit platforms.
- - [Fixed](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/260) excessive PNL checking after sort for spilling.
+ - [Fixed](https://libmdbx.dqdkfa.ru/dead-github/issues/260) excessive PNL checking after sort for spilling.
 - Reworked checking `MAX_PAGENO` and DB upper-size geometry limit.
- - [Fixed](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/265) build for some combinations of versions of  MSVC and Windows SDK.
+ - [Fixed](https://libmdbx.dqdkfa.ru/dead-github/issues/265) build for some combinations of versions of  MSVC and Windows SDK.

 Minors:

@@ -577,10 +799,10 @@ Acknowledgements:

 New features, extensions and improvements:

- - [Added](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/236) `mdbx_cursor_get_batch()`.
- - [Added](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/250) `MDBX_SET_UPPERBOUND`.
+ - [Added](https://libmdbx.dqdkfa.ru/dead-github/issues/236) `mdbx_cursor_get_batch()`.
+ - [Added](https://libmdbx.dqdkfa.ru/dead-github/issues/250) `MDBX_SET_UPPERBOUND`.
 - C++ API is finalized now.
- - The GC update stage has been [significantly speeded](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/254) when fixing huge Erigon's transactions (Ethereum ecosystem).
+ - The GC update stage has been [significantly speeded](https://libmdbx.dqdkfa.ru/dead-github/issues/254) when fixing huge Erigon's transactions (Ethereum ecosystem).

 Fixes:

@@ -591,12 +813,12 @@ Minors:

 - Fixed returning `MDBX_RESULT_TRUE` (unexpected -1) from `mdbx_env_set_option()`.
 - Added `mdbx_env_get_syncbytes()` and `mdbx_env_get_syncperiod()`.
- - [Clarified](https://web.archive.org/web/https://github.com/erthink/libmdbx/pull/249) description of `MDBX_INTEGERKEY`.
+ - [Clarified](https://libmdbx.dqdkfa.ru/dead-github/pull/249) description of `MDBX_INTEGERKEY`.
 - Reworked/simplified `mdbx_env_sync_internal()`.
- - [Fixed](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/248) extra assertion inside `mdbx_cursor_put()` for `MDBX_DUPFIXED` cases.
+ - [Fixed](https://libmdbx.dqdkfa.ru/dead-github/issues/248) extra assertion inside `mdbx_cursor_put()` for `MDBX_DUPFIXED` cases.
 - Avoiding extra looping inside `mdbx_env_info_ex()`.
 - Explicitly enabled core dumps from stochastic tests scripts on Linux.
- - [Fixed](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/253) `mdbx_override_meta()` to avoid false-positive assertions.
+ - [Fixed](https://libmdbx.dqdkfa.ru/dead-github/issues/253) `mdbx_override_meta()` to avoid false-positive assertions.
 - For compatibility reverted returning `MDBX_ENODATA`for some cases.


@@ -612,10 +834,10 @@ Acknowledgements:

 Fixes:

- - [Fixed compilation](https://web.archive.org/web/https://github.com/erthink/libmdbx/pull/239) with `devtoolset-9` on CentOS/RHEL 7.
- - [Fixed unexpected `MDBX_PROBLEM` error](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/242) because of update an obsolete meta-page.
- - [Fixed returning `MDBX_NOTFOUND` error](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/243) in case an inexact value found for `MDBX_GET_BOTH` operation.
- - [Fixed compilation](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/245) without kernel/libc-devel headers.
+ - [Fixed compilation](https://libmdbx.dqdkfa.ru/dead-github/pull/239) with `devtoolset-9` on CentOS/RHEL 7.
+ - [Fixed unexpected `MDBX_PROBLEM` error](https://libmdbx.dqdkfa.ru/dead-github/issues/242) because of update an obsolete meta-page.
+ - [Fixed returning `MDBX_NOTFOUND` error](https://libmdbx.dqdkfa.ru/dead-github/issues/243) in case an inexact value found for `MDBX_GET_BOTH` operation.
+ - [Fixed compilation](https://libmdbx.dqdkfa.ru/dead-github/issues/245) without kernel/libc-devel headers.

 Minors:

@@ -632,7 +854,7 @@ Minors:

 The database format signature has been changed to prevent
 forward-interoperability with an previous releases, which may lead to a
-[false positive diagnosis of database corruption](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/238)
+[false positive diagnosis of database corruption](https://libmdbx.dqdkfa.ru/dead-github/issues/238)
 due to flaws of an old library versions.

 This change is mostly invisible:
@@ -684,7 +906,7 @@ Acknowledgements:
 Fixes:

 - Fixed possibility of looping update GC during transaction commit (no public issue since the problem was discovered inside [Positive Technologies](https://www.ptsecurity.ru)).
- - Fixed `#pragma pack` to avoid provoking some compilers to generate code with [unaligned access](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/235).
+ - Fixed `#pragma pack` to avoid provoking some compilers to generate code with [unaligned access](https://libmdbx.dqdkfa.ru/dead-github/issues/235).
 - Fixed `noexcept` for potentially throwing `txn::put()` of C++ API.

 Minors:
@@ -710,7 +932,7 @@ Extensions and improvements:

 Fixes:

- - Always setup `madvise` while opening DB (fixes https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/231).
+ - Always setup `madvise` while opening DB (fixes https://libmdbx.dqdkfa.ru/dead-github/issues/231).
 - Fixed checking legacy `P_DIRTY` flag (`0x10`) for nested/sub-pages.

 Minors:
@@ -731,11 +953,11 @@ Acknowledgements:
 - [Lionel Debroux](https://github.com/debrouxl) for fuzzing tests and reporting bugs.
 - [Sergey Fedotov](https://github.com/SergeyFromHell/) for [`node-mdbx` NodeJS bindings](https://www.npmjs.com/package/node-mdbx).
 - [Kris Zyp](https://github.com/kriszyp) for [`lmdbx-store` NodeJS bindings](https://github.com/kriszyp/lmdbx-store).
- - [Noel Kuntze](https://github.com/Thermi) for [draft Python bindings](https://web.archive.org/web/https://github.com/erthink/libmdbx/commits/python-bindings).
+ - [Noel Kuntze](https://github.com/Thermi) for [draft Python bindings](https://libmdbx.dqdkfa.ru/dead-github/commits/python-bindings).

 New features, extensions and improvements:

- - [Allow to predefine/override `MDBX_BUILD_TIMESTAMP` for builds reproducibility](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/201).
+ - [Allow to predefine/override `MDBX_BUILD_TIMESTAMP` for builds reproducibility](https://libmdbx.dqdkfa.ru/dead-github/issues/201).
 - Added options support for `long-stochastic` script.
 - Avoided `MDBX_TXN_FULL` error for large transactions when possible.
 - The `MDBX_READERS_LIMIT` increased to `32767`.
@@ -743,7 +965,7 @@ New features, extensions and improvements:
 - Minimized the size of poisoned/unpoisoned regions to avoid Valgrind/ASAN stuck.
 - Added more workarounds for QEMU for testing builds for 32-bit platforms, Alpha and Sparc architectures.
 - `mdbx_chk` now skips iteration & checking of DB' records if corresponding page-tree is corrupted (to avoid `SIGSEGV`, ASAN failures, etc).
- - Added more checks for [rare/fuzzing corruption cases](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/217).
+ - Added more checks for [rare/fuzzing corruption cases](https://libmdbx.dqdkfa.ru/dead-github/issues/217).

 Backward compatibility break:

@@ -755,18 +977,18 @@ Backward compatibility break:
 Fixes:

 - Fixed excess meta-pages checks in case `mdbx_chk` is called to check the DB for a specific meta page and thus could prevent switching to the selected meta page, even if the check passed without errors.
- - Fixed [recursive use of SRW-lock on Windows cause by `MDBX_NOTLS` option](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/203).
- - Fixed [log a warning during a new DB creation](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/205).
- - Fixed [false-negative `mdbx_cursor_eof()` result](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/207).
- - Fixed [`make install` with non-GNU `install` utility (OSX, BSD)](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/208).
- - Fixed [installation by `CMake` in special cases by complete use `GNUInstallDirs`'s variables](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/209).
- - Fixed [C++ Buffer issue with `std::string` and alignment](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/191).
+ - Fixed [recursive use of SRW-lock on Windows cause by `MDBX_NOTLS` option](https://libmdbx.dqdkfa.ru/dead-github/issues/203).
+ - Fixed [log a warning during a new DB creation](https://libmdbx.dqdkfa.ru/dead-github/issues/205).
+ - Fixed [false-negative `mdbx_cursor_eof()` result](https://libmdbx.dqdkfa.ru/dead-github/issues/207).
+ - Fixed [`make install` with non-GNU `install` utility (OSX, BSD)](https://libmdbx.dqdkfa.ru/dead-github/issues/208).
+ - Fixed [installation by `CMake` in special cases by complete use `GNUInstallDirs`'s variables](https://libmdbx.dqdkfa.ru/dead-github/issues/209).
+ - Fixed [C++ Buffer issue with `std::string` and alignment](https://libmdbx.dqdkfa.ru/dead-github/issues/191).
 - Fixed `safe64_reset()` for platforms without atomic 64-bit compare-and-swap.
 - Fixed hang/shutdown on big-endian platforms without `__cxa_thread_atexit()`.
- - Fixed [using bad meta-pages if DB was partially/recoverable corrupted](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/217).
+ - Fixed [using bad meta-pages if DB was partially/recoverable corrupted](https://libmdbx.dqdkfa.ru/dead-github/issues/217).
 - Fixed extra `noexcept` for `buffer::&assign_reference()`.
 - Fixed `bootid` generation on Windows for case of change system' time.
- - Fixed [test framework keygen-related issue](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/127).
+ - Fixed [test framework keygen-related issue](https://libmdbx.dqdkfa.ru/dead-github/issues/127).


 ## v0.10.1 at 2021-06-01
@@ -787,10 +1009,10 @@ New features:
 Fixes:

 - Fixed minor "foo not used" warnings from modern C++ compilers when building the C++ part of the library.
- - Fixed confusing/messy errors when build library from unfit github's archives (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/197).
+ - Fixed confusing/messy errors when build library from unfit github's archives (https://libmdbx.dqdkfa.ru/dead-github/issues/197).
 - Fixed `#elsif` typo.
- - Fixed rare unexpected `MDBX_PROBLEM` error during altering data in huge transactions due to wrong spilling/oust of dirty pages (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/195).
- - Re-Fixed WSL1/WSL2 detection with distinguishing (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/97).
+ - Fixed rare unexpected `MDBX_PROBLEM` error during altering data in huge transactions due to wrong spilling/oust of dirty pages (https://libmdbx.dqdkfa.ru/dead-github/issues/195).
+ - Re-Fixed WSL1/WSL2 detection with distinguishing (https://libmdbx.dqdkfa.ru/dead-github/issues/97).


 ## v0.10.0 at 2021-05-09
@@ -813,7 +1035,7 @@ New features:
   and conjointly with the `MDBX_ENV_CHECKPID=0` and `MDBX_TXN_CHECKOWNER=0` options can yield
   up to 30% more performance compared to LMDB.
 - Using float point (exponential quantized) representation for internal 16-bit values
-   of grow step and shrink threshold when huge ones (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/166).
+   of grow step and shrink threshold when huge ones (https://libmdbx.dqdkfa.ru/dead-github/issues/166).
   To minimize the impact on compatibility, only the odd values inside the upper half
   of the range (i.e. 32769..65533) are used for the new representation.
 - Added the `mdbx_drop` similar to LMDB command-line tool to purge or delete (sub)database(s).
@@ -822,7 +1044,7 @@ New features:
 - The internal node sizes were refined, resulting in a reduction in large/overflow pages in some use cases
   and a slight increase in limits for a keys size to ≈½ of page size.
 - Added to `mdbx_chk` output number of keys/items on pages.
- - Added explicit `install-strip` and `install-no-strip` targets to the `Makefile` (https://web.archive.org/web/https://github.com/erthink/libmdbx/pull/180).
+ - Added explicit `install-strip` and `install-no-strip` targets to the `Makefile` (https://libmdbx.dqdkfa.ru/dead-github/pull/180).
 - Major rework page splitting (af9b7b560505684249b76730997f9e00614b8113) for
     - An "auto-appending" feature upon insertion for both ascending and
       descending key sequences. As a result, the optimality of page filling
@@ -830,7 +1052,7 @@ New features:
       inserting ordered sequences of keys,
     - A "splitting at middle" to make page tree more balanced on average.
 - Added `mdbx_get_sysraminfo()` to the API.
- - Added guessing a reasonable maximum DB size for the default upper limit of geometry (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/183).
+ - Added guessing a reasonable maximum DB size for the default upper limit of geometry (https://libmdbx.dqdkfa.ru/dead-github/issues/183).
 - Major rework internal labeling of a dirty pages (958fd5b9479f52f2124ab7e83c6b18b04b0e7dda) for
   a "transparent spilling" feature with the gist to make a dirty pages
   be ready to spilling (writing to a disk) without further altering ones.
@@ -846,7 +1068,7 @@ New features:
 - Support `make help` to list available make targets.
 - Silently `make`'s build by default.
 - Preliminary [Python bindings](https://github.com/Thermi/libmdbx/tree/python-bindings) is available now
-   by [Noel Kuntze](https://github.com/Thermi) (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/147).
+   by [Noel Kuntze](https://github.com/Thermi) (https://libmdbx.dqdkfa.ru/dead-github/issues/147).

 Backward compatibility break:

@@ -861,22 +1083,22 @@ Backward compatibility break:

 Fixes:

- - Fixed performance regression due non-optimal C11 atomics usage (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/160).
- - Fixed "reincarnation" of subDB after it deletion (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/168).
+ - Fixed performance regression due non-optimal C11 atomics usage (https://libmdbx.dqdkfa.ru/dead-github/issues/160).
+ - Fixed "reincarnation" of subDB after it deletion (https://libmdbx.dqdkfa.ru/dead-github/issues/168).
 - Fixed (disallowing) implicit subDB deletion via operations on `@MAIN`'s DBI-handle.
- - Fixed a crash of `mdbx_env_info_ex()` in case of a call for a non-open environment (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/171).
- - Fixed the selecting/adjustment values inside `mdbx_env_set_geometry()` for implicit out-of-range cases (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/170).
- - Fixed `mdbx_env_set_option()` for set initial and limit size of dirty page list ((https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/179).
- - Fixed an unreasonably huge default upper limit for DB geometry (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/183).
+ - Fixed a crash of `mdbx_env_info_ex()` in case of a call for a non-open environment (https://libmdbx.dqdkfa.ru/dead-github/issues/171).
+ - Fixed the selecting/adjustment values inside `mdbx_env_set_geometry()` for implicit out-of-range cases (https://libmdbx.dqdkfa.ru/dead-github/issues/170).
+ - Fixed `mdbx_env_set_option()` for set initial and limit size of dirty page list ((https://libmdbx.dqdkfa.ru/dead-github/issues/179).
+ - Fixed an unreasonably huge default upper limit for DB geometry (https://libmdbx.dqdkfa.ru/dead-github/issues/183).
 - Fixed `constexpr` specifier for the `slice::invalid()`.
- - Fixed (no)readahead auto-handling (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/164).
+ - Fixed (no)readahead auto-handling (https://libmdbx.dqdkfa.ru/dead-github/issues/164).
 - Fixed non-alloy build for Windows.
 - Switched to using Heap-functions instead of LocalAlloc/LocalFree on Windows.
- - Fixed `mdbx_env_stat_ex()` to returning statistics of the whole environment instead of MainDB only (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/190).
+ - Fixed `mdbx_env_stat_ex()` to returning statistics of the whole environment instead of MainDB only (https://libmdbx.dqdkfa.ru/dead-github/issues/190).
 - Fixed building by GCC 4.8.5 (added workaround for a preprocessor's bug).
 - Fixed building C++ part for iOS <= 13.0 (unavailability of  `std::filesystem::path`).
 - Fixed building for Windows target versions prior to Windows Vista (`WIN32_WINNT < 0x0600`).
- - Fixed building by MinGW for Windows (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/155).
+ - Fixed building by MinGW for Windows (https://libmdbx.dqdkfa.ru/dead-github/issues/155).


 -------------------------------------------------------------------------------
@@ -899,7 +1121,7 @@ Removed options and features:
 New features:

 - Package for FreeBSD is available now by Mahlon E. Smith.
- - New API functions to get/set various options (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/128):
+ - New API functions to get/set various options (https://libmdbx.dqdkfa.ru/dead-github/issues/128):
    - the maximum number of named databases for the environment;
    - the maximum number of threads/reader slots;
    - threshold (since the last unsteady commit) to force flush the data buffers to disk;
@@ -912,7 +1134,7 @@ New features:
    - maximal part of the dirty pages may be spilled when necessary;
    - minimal part of the dirty pages should be spilled when necessary;
    - how much of the parent transaction dirty pages will be spilled while start each child transaction;
- - Unlimited/Dynamic size of retired and dirty page lists (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/123).
+ - Unlimited/Dynamic size of retired and dirty page lists (https://libmdbx.dqdkfa.ru/dead-github/issues/123).
 - Added `-p` option (purge subDB before loading) to `mdbx_load` tool.
 - Reworked spilling of large transaction and committing of nested transactions:
    - page spilling code reworked to avoid the flaws and bugs inherited from LMDB;
@@ -922,22 +1144,22 @@ New features:
 - Added `MDBX_ENABLE_REFUND` and `MDBX_PNL_ASCENDING` internal/advanced build options.
 - Added `mdbx_default_pagesize()` function.
 - Better support architectures with a weak/relaxed memory consistency model (ARM, AARCH64, PPC, MIPS, RISC-V, etc) by means [C11 atomics](https://en.cppreference.com/w/c/atomic).
- - Speed up page number lists and dirty page lists (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/132).
+ - Speed up page number lists and dirty page lists (https://libmdbx.dqdkfa.ru/dead-github/issues/132).
 - Added `LIBMDBX_NO_EXPORTS_LEGACY_API` build option.

 Fixes:

- - Fixed missing cleanup (null assigned) in the C++ commit/abort (https://web.archive.org/web/https://github.com/erthink/libmdbx/pull/143).
+ - Fixed missing cleanup (null assigned) in the C++ commit/abort (https://libmdbx.dqdkfa.ru/dead-github/pull/143).
 - Fixed `mdbx_realloc()` for case of nullptr and `MDBX_WITHOUT_MSVC_CRT=ON` for Windows.
- - Fixed the possibility to use invalid and renewed (closed & re-opened, dropped & re-created) DBI-handles (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/146).
- - Fixed 4-byte aligned access to 64-bit integers, including access to the `bootid` meta-page's field (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/153).
+ - Fixed the possibility to use invalid and renewed (closed & re-opened, dropped & re-created) DBI-handles (https://libmdbx.dqdkfa.ru/dead-github/issues/146).
+ - Fixed 4-byte aligned access to 64-bit integers, including access to the `bootid` meta-page's field (https://libmdbx.dqdkfa.ru/dead-github/issues/153).
 - Fixed minor/potential memory leak during page flushing and unspilling.
 - Fixed handling states of cursors's and subDBs's for nested transactions.
 - Fixed page leak in extra rare case the list of retired pages changed during update GC on transaction commit.
- - Fixed assertions to avoid false-positive UB detection by CLANG/LLVM (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/153).
- - Fixed `MDBX_TXN_FULL` and regressive `MDBX_KEYEXIST` during large transaction commit with `MDBX_LIFORECLAIM` (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/123).
+ - Fixed assertions to avoid false-positive UB detection by CLANG/LLVM (https://libmdbx.dqdkfa.ru/dead-github/issues/153).
+ - Fixed `MDBX_TXN_FULL` and regressive `MDBX_KEYEXIST` during large transaction commit with `MDBX_LIFORECLAIM` (https://libmdbx.dqdkfa.ru/dead-github/issues/123).
 - Fixed auto-recovery (`weak->steady` with the same boot-id) when Database size at last weak checkpoint is large than at last steady checkpoint.
- - Fixed operation on systems with unusual small/large page size, including PowerPC (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/157).
+ - Fixed operation on systems with unusual small/large page size, including PowerPC (https://libmdbx.dqdkfa.ru/dead-github/issues/157).


 ## v0.9.2 at 2020-11-27
@@ -975,11 +1197,11 @@ Fixes:
 - Fixed copy&paste typos.
 - Fixed minor false-positive GCC warning.
 - Added workaround for broken `DEFINE_ENUM_FLAG_OPERATORS` from Windows SDK.
- - Fixed cursor state after multimap/dupsort repeated deletes (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/121).
+ - Fixed cursor state after multimap/dupsort repeated deletes (https://libmdbx.dqdkfa.ru/dead-github/issues/121).
 - Added `SIGPIPE` suppression for internal thread during `mdbx_env_copy()`.
- - Fixed extra-rare `MDBX_KEY_EXIST` error during `mdbx_commit()` (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/131).
- - Fixed spilled pages checking (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/126).
- - Fixed `mdbx_load` for 'plain text' and without `-s name` cases (https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/136).
+ - Fixed extra-rare `MDBX_KEY_EXIST` error during `mdbx_commit()` (https://libmdbx.dqdkfa.ru/dead-github/issues/131).
+ - Fixed spilled pages checking (https://libmdbx.dqdkfa.ru/dead-github/issues/126).
+ - Fixed `mdbx_load` for 'plain text' and without `-s name` cases (https://libmdbx.dqdkfa.ru/dead-github/issues/136).
 - Fixed save/restore/commit of cursors for nested transactions.
 - Fixed cursors state in rare/special cases (move next beyond end-of-data, after deletion and so on).
 - Added workaround for MSVC 19.28 (Visual Studio 16.8) (but may still hang during compilation).
@@ -1032,7 +1254,7 @@ Fixes:
 - Fix a lot of typos & spelling (Thanks to Josh Soref for PR).
 - Fix `getopt()` messages for Windows (Thanks to Andrey Sporaw for reporting).
 - Fix MSVC compiler version requirements (Thanks to Andrey Sporaw for reporting).
- - Workarounds for QEMU's bugs to run tests for cross-builded library under QEMU.
+ - Workarounds for QEMU's bugs to run tests for cross-built[A library under QEMU.
 - Now C++ compiler optional for building by CMake.


@@ -1101,7 +1323,7 @@ Deprecated functions and flags:
 - Avoid using `pwritev()` for single-writes (up to 10% speedup for some kernels & scenarios).
 - Avoiding `MDBX_UTTERLY_NOSYNC` as result of flags merge.
 - Add `mdbx_dbi_dupsort_depthmask()` function.
- - Add `MDBX_CP_FORCE_RESIZEABLE` option.
+ - Add `MDBX_CP_FORCE_RESIZABLE` option.
 - Add deprecated `MDBX_MAP_RESIZED` for compatibility.
 - Add `MDBX_BUILD_TOOLS` option (default `ON`).
 - Refine `mdbx_dbi_open_ex()` to safe concurrently opening the same handle from different threads.
--- a/41
+++ b/41
@@ -6,7 +6,7 @@
 #
 ################################################################################
 #
-# Basic internal definitios. For a customizable variables and options see below.
+# Basic internal definitions. For a customizable variables and options see below.
 #
 $(info // The GNU Make $(MAKE_VERSION))
 SHELL         := $(shell env bash -c 'echo $$BASH')
@@ -715,23 +715,23 @@ endif
 ################################################################################
 # Cross-compilation simple test

-CROSS_LIST = mips-linux-gnu-gcc \
+CROSS_LIST = \
+	mips64-linux-gnuabi64-gcc mips-linux-gnu-gcc \
+	hppa-linux-gnu-gcc s390x-linux-gnu-gcc \
 	powerpc64-linux-gnu-gcc powerpc-linux-gnu-gcc \
-	arm-linux-gnueabihf-gcc aarch64-linux-gnu-gcc \
-	sh4-linux-gnu-gcc mips64-linux-gnuabi64-gcc \
-	hppa-linux-gnu-gcc s390x-linux-gnu-gcc
+	arm-linux-gnueabihf-gcc aarch64-linux-gnu-gcc

-## On Ubuntu Focal (20.04) with QEMU 4.2 (1:4.2-3ubuntu6.6) & GCC 9.3 (9.3.0-17ubuntu1~20.04)
-# hppa-linux-gnu-gcc          - works (previously: don't supported by qemu)
-# s390x-linux-gnu-gcc         - works (previously: qemu hang/abort)
+## On Ubuntu Focal (22.04) with QEMU 6.2 (1:6.2+dfsg-2ubuntu6.6) & GCC 11.3 (11.3.0-1ubuntu1~22.04)
+# sh4-linux-gnu-gcc           - coredump (qemu mmap-troubles)
 # sparc64-linux-gnu-gcc       - coredump (qemu mmap-troubles, previously: qemu fails fcntl for F_SETLK/F_GETLK)
 # alpha-linux-gnu-gcc         - coredump (qemu mmap-troubles)
-CROSS_LIST_NOQEMU = sparc64-linux-gnu-gcc alpha-linux-gnu-gcc riscv64-linux-gnu-gcc
+# risc64-linux-gnu-gcc        - coredump (qemu qemu fails fcntl for F_SETLK/F_GETLK)
+CROSS_LIST_NOQEMU = sh4-linux-gnu-gcc sparc64-linux-gnu-gcc alpha-linux-gnu-gcc riscv64-linux-gnu-gcc

 cross-gcc:
 	@echo '  Re-building by cross-compiler for: $(CROSS_LIST_NOQEMU) $(CROSS_LIST)'
 	@echo "CORRESPONDING CROSS-COMPILERs ARE REQUIRED."
-	@echo "FOR INSTANCE: apt install g++-aarch64-linux-gnu g++-alpha-linux-gnu g++-arm-linux-gnueabihf g++-hppa-linux-gnu g++-mips-linux-gnu g++-mips64-linux-gnuabi64 g++-powerpc-linux-gnu g++-powerpc64-linux-gnu g++-s390x-linux-gnu g++-sh4-linux-gnu g++-sparc64-linux-gnu riscv64-linux-gnu-gcc"
+	@echo "FOR INSTANCE: sudo apt install \$$(apt list 'g++-*' | grep 'g++-[a-z0-9]\+-linux-gnu/' | cut -f 1 -d / | sort -u)"
 	$(QUIET)for CC in $(CROSS_LIST_NOQEMU) $(CROSS_LIST); do \
 		echo "===================== $$CC"; \
 		$(MAKE) IOARENA=false CXXSTD= clean && CC=$$CC CXX=$$(echo $$CC | sed 's/-gcc/-g++/') EXE_LDFLAGS=-static $(MAKE) IOARENA=false all || exit $$?; \
@@ -743,8 +743,8 @@ cross-qemu:
 	@echo '  Re-building by cross-compiler and re-check by QEMU for: $(CROSS_LIST)'
 	@echo "CORRESPONDING CROSS-COMPILERs AND QEMUs ARE REQUIRED."
 	@echo "FOR INSTANCE: "
-	@echo "	1) apt install g++-aarch64-linux-gnu g++-alpha-linux-gnu g++-arm-linux-gnueabihf g++-hppa-linux-gnu g++-mips-linux-gnu g++-mips64-linux-gnuabi64 g++-powerpc-linux-gnu g++-powerpc64-linux-gnu g++-s390x-linux-gnu g++-sh4-linux-gnu g++-sparc64-linux-gnu"
-	@echo "	2) apt install binfmt-support qemu-user-static qemu-user qemu-system-arm qemu-system-mips qemu-system-misc qemu-system-ppc qemu-system-sparc"
+	@echo "	1) sudo apt install \$$(apt list 'g++-*' | grep 'g++-[a-z0-9]\+-linux-gnu/' | cut -f 1 -d / | sort -u)"
+	@echo "	2) sudo apt install binfmt-support qemu-user-static qemu-user \$$(apt list 'qemu-system-*' | grep 'qemu-system-[a-z0-9]\+/' | cut -f 1 -d / | sort -u)"
 	$(QUIET)for CC in $(CROSS_LIST); do \
 		echo "===================== $$CC + qemu"; \
 		$(MAKE) IOARENA=false CXXSTD= clean && \
@@ -788,7 +788,7 @@ IOARENA := $(shell \
  (test -x ../ioarena/@BUILD/src/ioarena && echo ../ioarena/@BUILD/src/ioarena) || \
  (test -x ../../@BUILD/src/ioarena && echo ../../@BUILD/src/ioarena) || \
  (test -x ../../src/ioarena && echo ../../src/ioarena) || which ioarena 2>&- || \
-  (echo false && echo '$(TIP) Clone and build the https://github.com/pmwkaa/ioarena.git within a neighbouring directory for availability of benchmarking.' >&2))
+  (echo false && echo '$(TIP) Clone and build the https://abf.io/erthink/ioarena.git within a neighbouring directory for availability of benchmarking.' >&2))
 endif
 NN	?= 25000000
 BENCH_CRUD_MODE ?= nosync
@@ -802,7 +802,7 @@ re-bench: bench-clean bench
 ifeq ($(or $(IOARENA),false),false)
 bench bench-quartet bench-triplet bench-couple:
 	$(QUIET)echo 'The `ioarena` benchmark is required.' >&2 && \
-	echo 'Please clone and build the https://github.com/pmwkaa/ioarena.git within a neighbouring `ioarena` directory.' >&2 && \
+	echo 'Please clone and build the https://abf.io/erthink/ioarena.git within a neighbouring `ioarena` directory.' >&2 && \
 	false

 else
@@ -813,15 +813,20 @@ define bench-rule
 bench-$(1)_$(2).txt: $(3) $(IOARENA) $(lastword $(MAKEFILE_LIST))
 	@echo '  RUNNING ioarena for $1/$2...'
 	$(QUIET)(export LD_LIBRARY_PATH="./:$$$${LD_LIBRARY_PATH}"; \
-		ldd $(IOARENA) && \
+		ldd $(IOARENA) | grep -i $(1) && \
+		$(IOARENA) -D $(1) -B batch -m $(BENCH_CRUD_MODE) -n $(2) \
+			| tee $$@ | grep throughput | sed 's/throughput/batch×N/' && \
 		$(IOARENA) -D $(1) -B crud -m $(BENCH_CRUD_MODE) -n $(2) \
-			| tee $$@ | grep throughput && \
+			| tee -a $$@ | grep throughput | sed 's/throughput/   crud/' && \
 		$(IOARENA) -D $(1) -B iterate,get,iterate,get,iterate -m $(BENCH_CRUD_MODE) -r 4 -n $(2) \
-			| tee -a $$@ | grep throughput \
-	) || mv -f $$@ $$@.error
+			| tee -a $$@ | grep throughput | sed '0,/throughput/{s/throughput/iterate/};s/throughput/    get/' && \
+		$(IOARENA) -D $(1) -B delete -m $(BENCH_CRUD_MODE) -n $(2) \
+			| tee -a $$@ | grep throughput | sed 's/throughput/ delete/' && \
+	true) || mv -f $$@ $$@.error

 endef

+
 $(eval $(call bench-rule,mdbx,$(NN),libmdbx.$(SO_SUFFIX)))

 $(eval $(call bench-rule,sophia,$(NN)))
--- a/README.md
+++ b/README.md
@@ -81,19 +81,48 @@ Historically, _libmdbx_ is a deeply revised and extended descendant of the amazi
 [Lightning Memory-Mapped Database](https://en.wikipedia.org/wiki/Lightning_Memory-Mapped_Database).
 _libmdbx_ inherits all benefits from _LMDB_, but resolves some issues and adds [a set of improvements](#improvements-beyond-lmdb).

+### MithrilDB and Future
+
 <!-- section-begin mithril -->

-The next version is under active non-public development from scratch and will be
+The next version is under non-public development from scratch and will be
 released as **MithrilDB** and `libmithrildb` for libraries & packages.
 Admittedly mythical [Mithril](https://en.wikipedia.org/wiki/Mithril) is
 resembling silver but being stronger and lighter than steel. Therefore
 _MithrilDB_ is a rightly relevant name.

-   > _MithrilDB_ will be radically different from _libmdbx_ by the new
-   > database format and API based on C++17, as well as the [Apache 2.0
-   > License](https://www.apache.org/licenses/LICENSE-2.0). The goal of this
-   > revolution is to provide a clearer and robust API, add more features and
-   > new valuable properties of the database.
+_MithrilDB_ is radically different from _libmdbx_ by the new database
+format and API based on C++20. The goal of this revolution is to provide
+a clearer and robust API, add more features and new valuable properties
+of the database. All fundamental architectural problems of libmdbx/LMDB
+have been solved there, but now the active development has been
+suspended for top-three reasons:
+
+1. For now _libmdbx_ «mostly» enough for all [our products](https://www.ptsecurity.com/ww-en/products/),
+and I’m busy in development of replication for scalability.
+2. Waiting for fresh [Elbrus CPU](https://wiki.elbrus.ru/) of [e2k architecture](https://en.wikipedia.org/wiki/Elbrus_2000),
+especially with hardware acceleration of [Streebog](https://en.wikipedia.org/wiki/Streebog) and
+[Kuznyechik](https://en.wikipedia.org/wiki/Kuznyechik), which are required for Merkle tree, etc.
+3. The expectation of needs and opportunities due to the wide use of NVDIMM (aka persistent memory),
+modern NVMe and [Ангара](https://ru.wikipedia.org/wiki/Ангара_(интерконнект)).
+
+However, _MithrilDB_ will not be available for countries unfriendly to
+Russia (i.e. acceded the sanctions, devil adepts and/or NATO). But it is
+not yet known whether such restriction will be implemented only through
+a license and support, either the source code will not be open at all.
+Basically we are not inclined to allow our work to contribute to the
+profit that goes to weapons that kill our relatives and friends.
+NO OPTIONS.
+
+Nonetheless, I try not to make any promises regarding _MithrilDB_ until release.
+
+Contrary to _MithrilDB_, _libmdbx_ will forever free and open source.
+Moreover with high-quality support whenever possible. Tu deviens
+responsable pour toujours de ce que tu as apprivois. So we will continue
+to comply with the original open license and the principles of
+constructive cooperation, in spite of outright Github sabotage and
+sanctions. I will also try to keep (not drop) Windows support, despite
+it is an unused obsolete technology for us.

 <!-- section-end -->

@@ -248,7 +277,7 @@ the user's point of view.
   > and up to 30% faster when _libmdbx_ compiled with specific build options
   > which downgrades several runtime checks to be match with LMDB behaviour.
   >
-   > These and other results could be easily reproduced with [ioArena](https://github.com/pmwkaa/ioarena) just by `make bench-quartet` command,
+   > These and other results could be easily reproduced with [ioArena](https://abf.io/erthink/ioarena.git) just by `make bench-quartet` command,
   > including comparisons with [RockDB](https://en.wikipedia.org/wiki/RocksDB)
   > and [WiredTiger](https://en.wikipedia.org/wiki/WiredTiger).

@@ -435,7 +464,7 @@ unexpected or broken down.

 ### Testing
 The amalgamated source code does not contain any tests for or several reasons.
-Please read [the explanation](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/214#issuecomment-870717981) and don't ask to alter this.
+Please read [the explanation](https://libmdbx.dqdkfa.ru/dead-github/issues/214#issuecomment-870717981) and don't ask to alter this.
 So for testing _libmdbx_ itself you need a full source code, i.e. the clone of a git repository, there is no option.

 The full source code of _libmdbx_ has a [`test` subdirectory](https://gitflic.ru/project/erthink/libmdbx/tree/master/test) with minimalistic test "framework".
@@ -618,7 +647,7 @@ Bindings
 | Rust    | [libmdbx-rs](https://github.com/vorot93/libmdbx-rs)   | [Artem Vorotnikov](https://github.com/vorot93) |
 | Rust    | [mdbx](https://crates.io/crates/mdbx)                 | [gcxfd](https://github.com/gcxfd) |
 | Java    | [mdbxjni](https://github.com/castortech/mdbxjni)      | [Castor Technologies](https://castortech.com/) |
-| Python (draft)  | [python-bindings](https://web.archive.org/web/https://github.com/erthink/libmdbx/commits/python-bindings) branch | [Noel Kuntze](https://github.com/Thermi)
+| Python (draft)  | [python-bindings](https://libmdbx.dqdkfa.ru/dead-github/commits/python-bindings) branch | [Noel Kuntze](https://github.com/Thermi)
 | .NET (obsolete) | [mdbx.NET](https://github.com/wangjia184/mdbx.NET) | [Jerry Wang](https://github.com/wangjia184) |

 <!-- section-end -->
@@ -630,7 +659,7 @@ Bindings
 Performance comparison
 ======================

-All benchmarks were done in 2015 by [IOArena](https://github.com/pmwkaa/ioarena)
+All benchmarks were done in 2015 by [IOArena](https://abf.io/erthink/ioarena.git)
 and multiple [scripts](https://github.com/pmwkaa/ioarena/tree/HL%2B%2B2015)
 runs on Lenovo Carbon-2 laptop, i7-4600U 2.1 GHz (2 physical cores, 4 HyperThreading cores), 8 Gb RAM,
 SSD SAMSUNG MZNTD512HAGL-000L1 (DXT23L0Q) 512 Gb.
--- a/TODO.md
+++ b/TODO.md
@@ -11,19 +11,19 @@ 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://web.archive.org/web/https://github.com/erthink/libmdbx/issues/204).
- - [Replace SRW-lock on Windows to allow shrink DB with `MDBX_NOTLS` option](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/210).
- - [More flexible support of asynchronous runtime/framework(s)](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/200).
- - [Migration guide from LMDB to MDBX](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/199).
- - [Support for RAW devices](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/124).
- - [Support MessagePack for Keys & Values](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/115).
- - [Engage new terminology](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/137).
+ - [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).
+ - [Support for RAW devices](https://libmdbx.dqdkfa.ru/dead-github/issues/124).
+ - [Support MessagePack for Keys & Values](https://libmdbx.dqdkfa.ru/dead-github/issues/115).
+ - [Engage new terminology](https://libmdbx.dqdkfa.ru/dead-github/issues/137).
 - Packages for [Astra Linux](https://astralinux.ru/), [ALT Linux](https://www.altlinux.org/), [ROSA Linux](https://www.rosalinux.ru/), etc.

 Done
 ----

- - [Simple careful mode for working with corrupted DB](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/223).
- - [Engage an "overlapped I/O" on Windows](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/224).
- - [Large/Overflow pages accounting for dirty-room](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/192).
- - [Get rid of dirty-pages list in MDBX_WRITEMAP mode](https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/193).
+ - [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).
+ - [Get rid of dirty-pages list in MDBX_WRITEMAP mode](https://libmdbx.dqdkfa.ru/dead-github/issues/193).
--- a/cmake/compiler.cmake
+++ b/cmake/compiler.cmake
@@ -1,4 +1,4 @@
-##  Copyright (c) 2012-2022 Leonid Yuriev <leo@yuriev.ru>.
+##  Copyright (c) 2012-2023 Leonid Yuriev <leo@yuriev.ru>.
 ##
 ##  Licensed under the Apache License, Version 2.0 (the "License");
 ##  you may not use this file except in compliance with the License.
@@ -348,6 +348,8 @@ endif()

 if(MSVC)
  check_compiler_flag("/WX" CC_HAS_WERROR)
+  check_compiler_flag("/fsanitize=address" CC_HAS_ASAN)
+  check_compiler_flag("/fsanitize=undefined" CC_HAS_UBSAN)
 else()
  #
  # GCC started to warn for unused result starting from 4.2, and
@@ -839,19 +841,26 @@ macro(setup_compile_flags)
  endif()

  if(ENABLE_ASAN)
-    add_compile_flags("C;CXX" "-fsanitize=address")
+    if(NOT MSVC)
+      add_compile_flags("C;CXX" "-fsanitize=address")
+    else()
+      add_compile_flags("C;CXX" "/fsanitize=address")
+    endif()
    add_definitions(-DASAN_ENABLED=1)
  endif()

  if(ENABLE_UBSAN)
-    add_compile_flags("C;CXX" "-fsanitize=undefined" "-fsanitize-undefined-trap-on-error")
+    if(NOT MSVC)
+      add_compile_flags("C;CXX" "-fsanitize=undefined" "-fsanitize-undefined-trap-on-error")
+    else()
+      add_compile_flags("C;CXX" "/fsanitize=undefined")
+    endif()
    add_definitions(-DUBSAN_ENABLED=1)
  endif()

  if(ENABLE_GCOV)
    if(NOT HAVE_GCOV)
-      message(FATAL_ERROR
-        "ENABLE_GCOV option requested but gcov library is not found")
+      message(FATAL_ERROR "ENABLE_GCOV option requested but gcov library is not found")
    endif()

    add_compile_flags("C;CXX" "-fprofile-arcs" "-ftest-coverage")
--- a/cmake/profile.cmake
+++ b/cmake/profile.cmake
@@ -1,4 +1,4 @@
-##  Copyright (c) 2012-2022 Leonid Yuriev <leo@yuriev.ru>.
+##  Copyright (c) 2012-2023 Leonid Yuriev <leo@yuriev.ru>.
 ##
 ##  Licensed under the Apache License, Version 2.0 (the "License");
 ##  you may not use this file except in compliance with the License.
--- a/cmake/utils.cmake
+++ b/cmake/utils.cmake
@@ -1,4 +1,4 @@
-##  Copyright (c) 2012-2022 Leonid Yuriev <leo@yuriev.ru>.
+##  Copyright (c) 2012-2023 Leonid Yuriev <leo@yuriev.ru>.
 ##
 ##  Licensed under the Apache License, Version 2.0 (the "License");
 ##  you may not use this file except in compliance with the License.
--- a/docs/_starting.md
+++ b/docs/_starting.md
@@ -67,7 +67,7 @@ the end is hit.
 To retrieve all keys starting from a specified key value, use \ref MDBX_SET. For
 more cursor operations, see the \ref c_api reference.

-When using \ref mdbx_cursor_put()\ref , either the function will position the cursor
+When using \ref mdbx_cursor_put(), either the function will position the cursor
 for you based on the key, or you can use operation \ref MDBX_CURRENT to use the
 current position of the cursor. \note Note that key must then match the current
 position's key.
--- a/docs/_toc.md
+++ b/docs/_toc.md
@@ -38,4 +38,4 @@ including creating [merge-request](https://gitflic.ru/project/erthink/libmdbx/me

 ---

-\section MithrilDB MithrilDB
+\section MithrilDB MithrilDB and Future
--- a/example/example-mdbx.c
+++ b/example/example-mdbx.c
@@ -4,7 +4,7 @@
 */

 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>.
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>.
 * Copyright 2017 Ilya Shipitsin <chipitsine@gmail.com>.
 * Copyright 2012-2015 Howard Chu, Symas Corp.
 * All rights reserved.
--- a/example/sample-bdb.txt
+++ b/example/sample-bdb.txt
@@ -4,7 +4,7 @@
 */

 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>.
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>.
 * Copyright 2012-2015 Howard Chu, Symas Corp.
 * Copyright 2015,2016 Peter-Service R&D LLC.
 * All rights reserved.
--- a/mdbx.h
+++ b/mdbx.h
@@ -25,7 +25,7 @@ _The Future will (be) [Positive](https://www.ptsecurity.com). Всё будет

 \section copyright LICENSE & COPYRIGHT

-\authors Copyright (c) 2015-2022, Leonid Yuriev <leo@yuriev.ru>
+\authors Copyright (c) 2015-2023, Leonid Yuriev <leo@yuriev.ru>
 and other _libmdbx_ authors: please see [AUTHORS](./AUTHORS) file.

 \copyright Redistribution and use in source and binary forms, with or without
@@ -77,10 +77,10 @@ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 #if defined(__riscv) || defined(__riscv__) || defined(__RISCV) ||              \
    defined(__RISCV__)
-#warning The RISC-V architecture is intentionally insecure by design. \
+#warning "The RISC-V architecture is intentionally insecure by design. \
  Please delete this admonition at your own risk, \
  if you make such decision informed and consciously. \
-  Refer to https://clck.ru/32d9xH for more information.
+  Refer to https://clck.ru/32d9xH for more information."
 #endif /* RISC-V */

 #ifdef _MSC_VER
@@ -695,11 +695,11 @@ extern LIBMDBX_VERINFO_API const struct MDBX_build_info {
 * automatically (de)initialization, releasing reader lock table slots
 * and so on.
 *
- * If MDBX builded as a DLL this is done out-of-the-box by DllEntry() function,
+ * If MDBX built as a DLL this is done out-of-the-box by DllEntry() function,
 * which called automatically by Windows core with passing corresponding reason
 * argument.
 *
- * Otherwise, if MDBX was builded not as a DLL, some black magic
+ * Otherwise, if MDBX was built not as a DLL, some black magic
 * may be required depending of Windows version:
 *
 *  - Modern Windows versions, including Windows Vista and later, provides
@@ -881,7 +881,7 @@ enum MDBX_constants {
 /* DEBUG & LOGGING ************************************************************/

 /** \addtogroup c_debug
- * \note Most of debug feature enabled only when libmdbx builded with
+ * \note Most of debug feature enabled only when libmdbx built with
 * \ref MDBX_DEBUG build option. @{ */

 /** Log level
@@ -946,7 +946,7 @@ typedef enum MDBX_log_level_t MDBX_log_level_t;
 *
 * \details `MDBX_DBG_DUMP` and `MDBX_DBG_LEGACY_MULTIOPEN` always have an
 * effect, but `MDBX_DBG_ASSERT`, `MDBX_DBG_AUDIT` and `MDBX_DBG_JITTER` only if
- * libmdbx builded with \ref MDBX_DEBUG. */
+ * libmdbx built with \ref MDBX_DEBUG. */
 enum MDBX_debug_flags_t {
  MDBX_DBG_NONE = 0,

@@ -1682,7 +1682,7 @@ enum MDBX_copy_flags_t {
   * pages sequentially */
  MDBX_CP_COMPACT = 1u,

-  /** Force to make resizeable copy, i.e. dynamic size instead of fixed */
+  /** Force to make resizable copy, i.e. dynamic size instead of fixed */
  MDBX_CP_FORCE_DYNAMIC_SIZE = 2u
 };
 #ifndef __cplusplus
@@ -1926,6 +1926,15 @@ enum MDBX_error_t {
  /** Overlapping read and write transactions for the current thread */
  MDBX_TXN_OVERLAPPING = -30415,

+  /** Внутренняя ошибка возвращаемая в случае нехватки запаса свободных страниц
+   * при обновлении GC. Используется как вспомогательное средство для отладки.
+   * \note С точки зрения пользователя семантически
+   *       равнозначна \ref MDBX_PROBLEM. */
+  MDBX_BACKLOG_DEPLETED = -30414,
+
+  /** Alternative/Duplicate LCK-file is exists and should be removed manually */
+  MDBX_DUPLICATED_CLK = -30413,
+
  /* The last of MDBX-added error codes */
  MDBX_LAST_ADDED_ERRCODE = MDBX_TXN_OVERLAPPING,

@@ -2051,7 +2060,9 @@ LIBMDBX_API const char *mdbx_strerror_r_ANSI2OEM(int errnum, char *buf,
 * \returns a non-zero error value on failure and 0 on success. */
 LIBMDBX_API int mdbx_env_create(MDBX_env **penv);

-/** \brief MDBX environment options. */
+/** \brief MDBX environment extra runtime options.
+ * \ingroup c_settings
+ * \see mdbx_env_set_option() \see mdbx_env_get_option() */
 enum MDBX_option_t {
  /** \brief Controls the maximum number of named databases for the environment.
   *
@@ -2220,13 +2231,46 @@ enum MDBX_option_t {
   * to 50% (half empty) which corresponds to the range from 8192 and to 32768
   * in units respectively. */
  MDBX_opt_merge_threshold_16dot16_percent,
+
+  /** \brief Controls the choosing between use write-through disk writes and
+   * usual ones with followed flush by the `fdatasync()` syscall.
+   * \details Depending on the operating system, storage subsystem
+   * characteristics and the use case, higher performance can be achieved by
+   * either using write-through or a serie of usual/lazy writes followed by
+   * the flush-to-disk.
+   *
+   * Basically for N chunks the latency/cost of write-through is:
+   *  latency = N * (emit + round-trip-to-storage + storage-execution);
+   * And for serie of lazy writes with flush is:
+   *  latency = N * (emit + storage-execution) + flush + round-trip-to-storage.
+   *
+   * So, for large N and/or noteable round-trip-to-storage the write+flush
+   * approach is win. But for small N and/or near-zero NVMe-like latency
+   * the write-through is better.
+   *
+   * To solve this issue libmdbx provide `MDBX_opt_writethrough_threshold`:
+   *  - when N described above less or equal specified threshold,
+   *    a write-through approach will be used;
+   *  - otherwise, when N great than specified threshold,
+   *    a write-and-flush approach will be used.
+   *
+   * \note MDBX_opt_writethrough_threshold affects only \ref MDBX_SYNC_DURABLE
+   * mode without \ref MDBX_WRITEMAP, and not supported on Windows.
+   * On Windows a write-through is used always but \ref MDBX_NOMETASYNC could
+   * be used for switching to write-and-flush. */
+  MDBX_opt_writethrough_threshold,
+
+  /** \brief Controls prevention of page-faults of reclaimed and allocated pages
+   * in the \ref MDBX_WRITEMAP mode by clearing ones through file handle before
+   * touching. */
+  MDBX_opt_prefault_write_enable,
 };
 #ifndef __cplusplus
 /** \ingroup c_settings */
 typedef enum MDBX_option_t MDBX_option_t;
 #endif

-/** \brief Sets the value of a runtime options for an environment.
+/** \brief Sets the value of a extra runtime options for an environment.
 * \ingroup c_settings
 *
 * \param [in] env     An environment handle returned by \ref mdbx_env_create().
@@ -2239,7 +2283,7 @@ typedef enum MDBX_option_t MDBX_option_t;
 LIBMDBX_API int mdbx_env_set_option(MDBX_env *env, const MDBX_option_t option,
                                    uint64_t value);

-/** \brief Gets the value of runtime options from an environment.
+/** \brief Gets the value of extra runtime options from an environment.
 * \ingroup c_settings
 *
 * \param [in] env     An environment handle returned by \ref mdbx_env_create().
@@ -2260,6 +2304,8 @@ LIBMDBX_API int mdbx_env_get_option(const MDBX_env *env,
 * be called later to discard the \ref MDBX_env handle and release associated
 * resources.
 *
+ * \note On Windows the \ref mdbx_env_openW() is recommended to use.
+ *
 * \param [in] env       An environment handle returned
 *                       by \ref mdbx_env_create()
 *
@@ -2327,8 +2373,11 @@ LIBMDBX_API int mdbx_env_get_option(const MDBX_env *env,
 LIBMDBX_API int mdbx_env_open(MDBX_env *env, const char *pathname,
                              MDBX_env_flags_t flags, mdbx_mode_t mode);

-#if defined(_WIN32) || defined(_WIN64)
-LIBMDBX_API int mdbx_env_openW(MDBX_env *env, const wchar_t *pathnameW,
+#if defined(_WIN32) || defined(_WIN64) || defined(DOXYGEN)
+/** \copydoc mdbx_env_open()
+ * \note Available only on Windows.
+ * \see mdbx_env_open() */
+LIBMDBX_API int mdbx_env_openW(MDBX_env *env, const wchar_t *pathname,
                               MDBX_env_flags_t flags, mdbx_mode_t mode);
 #endif /* Windows */

@@ -2358,6 +2407,8 @@ typedef enum MDBX_env_delete_mode_t MDBX_env_delete_mode_t;
 /** \brief Delete the environment's files in a proper and multiprocess-safe way.
 * \ingroup c_extra
 *
+ * \note On Windows the \ref mdbx_env_deleteW() is recommended to use.
+ *
 * \param [in] pathname  The pathname for the database or the directory in which
 *                       the database files reside.
 *
@@ -2374,8 +2425,12 @@ typedef enum MDBX_env_delete_mode_t MDBX_env_delete_mode_t;
 *                            so no deletion was performed. */
 LIBMDBX_API int mdbx_env_delete(const char *pathname,
                                MDBX_env_delete_mode_t mode);
-#if defined(_WIN32) || defined(_WIN64)
-LIBMDBX_API int mdbx_env_deleteW(const wchar_t *pathnameW,
+
+#if defined(_WIN32) || defined(_WIN64) || defined(DOXYGEN)
+/** \copydoc mdbx_env_delete()
+ * \note Available only on Windows.
+ * \see mdbx_env_delete() */
+LIBMDBX_API int mdbx_env_deleteW(const wchar_t *pathname,
                                 MDBX_env_delete_mode_t mode);
 #endif /* Windows */

@@ -2388,6 +2443,8 @@ LIBMDBX_API int mdbx_env_deleteW(const wchar_t *pathnameW,
 * parallel with write transactions, because it employs a read-only
 * transaction. See long-lived transactions under \ref restrictions section.
 *
+ * \note On Windows the \ref mdbx_env_copyW() is recommended to use.
+ *
 * \param [in] env    An environment handle returned by mdbx_env_create().
 *                    It must have already been opened successfully.
 * \param [in] dest   The pathname of a file in which the copy will reside.
@@ -2407,12 +2464,16 @@ LIBMDBX_API int mdbx_env_deleteW(const wchar_t *pathnameW,
 *      account skipping free pages.
 *
 *  - \ref MDBX_CP_FORCE_DYNAMIC_SIZE
- *      Force to make resizeable copy, i.e. dynamic size instead of fixed.
+ *      Force to make resizable copy, i.e. dynamic size instead of fixed.
 *
 * \returns A non-zero error value on failure and 0 on success. */
 LIBMDBX_API int mdbx_env_copy(MDBX_env *env, const char *dest,
                              MDBX_copy_flags_t flags);
-#if defined(_WIN32) || defined(_WIN64)
+
+#if defined(_WIN32) || defined(_WIN64) || defined(DOXYGEN)
+/** \copydoc mdbx_env_copy()
+ * \note Available only on Windows.
+ * \see mdbx_env_copy() */
 LIBMDBX_API int mdbx_env_copyW(MDBX_env *env, const wchar_t *dest,
                               MDBX_copy_flags_t flags);
 #endif /* Windows */
@@ -2555,16 +2616,18 @@ struct MDBX_envinfo {
   * first process opened the database after everyone had previously closed it).
   */
  struct {
-    uint64_t newly;   /**< Quantity of a new pages added */
-    uint64_t cow;     /**< Quantity of pages copied for update */
-    uint64_t clone;   /**< Quantity of parent's dirty pages clones
-                           for nested transactions */
-    uint64_t split;   /**< Page splits */
-    uint64_t merge;   /**< Page merges */
-    uint64_t spill;   /**< Quantity of spilled dirty pages */
-    uint64_t unspill; /**< Quantity of unspilled/reloaded pages */
-    uint64_t wops;    /**< Number of explicit write operations (not a pages)
-                           to a disk */
+    uint64_t newly;    /**< Quantity of a new pages added */
+    uint64_t cow;      /**< Quantity of pages copied for update */
+    uint64_t clone;    /**< Quantity of parent's dirty pages clones
+                            for nested transactions */
+    uint64_t split;    /**< Page splits */
+    uint64_t merge;    /**< Page merges */
+    uint64_t spill;    /**< Quantity of spilled dirty pages */
+    uint64_t unspill;  /**< Quantity of unspilled/reloaded pages */
+    uint64_t wops;     /**< Number of explicit write operations (not a pages)
+                            to a disk */
+    uint64_t prefault; /**< Number of prefault write operations (not a pages) */
+    uint64_t mincore;  /**< Number of mincore() calls */
    uint64_t
        msync; /**< Number of explicit msync-to-disk operations (not a pages) */
    uint64_t
@@ -2863,7 +2926,7 @@ enum MDBX_warmup_flags_t {
  MDBX_warmup_lock = 4,

  /** Alters corresponding current resource limits to be enough for lock pages
-   * by \ref MDBX_warmup_lock. However, this option should be used in simpliest
+   * by \ref MDBX_warmup_lock. However, this option should be used in simpler
   * applications since takes into account only current size of this environment
   * disregarding all other factors. For real-world database application you
   * will need full-fledged management of resources and their limits with
@@ -2899,7 +2962,7 @@ DEFINE_ENUM_FLAG_OPERATORS(MDBX_warmup_flags_t)
 * \param [in] timeout_seconds_16dot16  Optional timeout which checking only
 *                              during explicitly peeking database pages
 *                              for loading ones if the \ref MDBX_warmup_force
- *                              option was spefified.
+ *                              option was specified.
 *
 * \returns A non-zero error value on failure and 0 on success.
 * Some possible errors are:
@@ -2951,6 +3014,8 @@ LIBMDBX_API int mdbx_env_get_flags(const MDBX_env *env, unsigned *flags);
 /** \brief Return the path that was used in mdbx_env_open().
 * \ingroup c_statinfo
 *
+ * \note On Windows the \ref mdbx_env_get_pathW() is recommended to use.
+ *
 * \param [in] env     An environment handle returned by \ref mdbx_env_create()
 * \param [out] dest   Address of a string pointer to contain the path.
 *                     This is the actual string in the environment, not a
@@ -2959,9 +3024,12 @@ LIBMDBX_API int mdbx_env_get_flags(const MDBX_env *env, unsigned *flags);
 * \returns A non-zero error value on failure and 0 on success,
 *          some possible errors are:
 * \retval MDBX_EINVAL  An invalid parameter was specified. */
-#if !(defined(_WIN32) || defined(_WIN64))
 LIBMDBX_API int mdbx_env_get_path(const MDBX_env *env, const char **dest);
-#else
+
+#if defined(_WIN32) || defined(_WIN64) || defined(DOXYGEN)
+/** \copydoc mdbx_env_get_path()
+ * \note Available only on Windows.
+ * \see mdbx_env_get_path() */
 LIBMDBX_API int mdbx_env_get_pathW(const MDBX_env *env, const wchar_t **dest);
 #endif /* Windows */

@@ -3027,7 +3095,7 @@ LIBMDBX_API int mdbx_env_get_fd(const MDBX_env *env, mdbx_filehandle_t *fd);
 *    was called after \ref mdbx_env_open() but OUTSIDE a write transaction,
 *    then MDBX will execute internal pseudo-transaction to apply new parameters
 *    (but only if anything has been changed), and changes be visible to any
- *    others processes immediately after succesful completion of function.
+ *    others processes immediately after successful completion of function.
 *
 * Essentially a concept of "automatic size management" is simple and useful:
 *  - There are the lower and upper bounds of the database file size;
@@ -3766,13 +3834,10 @@ struct MDBX_commit_latency {
    /** \brief Время "по настенным часам" затраченное на чтение и поиск внутри
     *  GC ради данных пользователя. */
    uint32_t work_rtime_monotonic;
-    /** \brief Монотонное время по "настенным часам" затраченное
+    /** \brief Время ЦПУ в режиме пользователе затраченное
     *   на подготовку страниц извлекаемых из GC для данных пользователя,
     *   включая подкачку с диска. */
-    uint32_t work_xtime_monotonic;
-    /** \brief Время ЦПУ в режиме пользователе затраченное на чтение и поиск
-     *  внтури GC ради данных пользователя. */
-    uint32_t work_rtime_cpu;
+    uint32_t work_xtime_cpu;
    /** \brief Количество итераций поиска внутри GC при выделении страниц
     *  ради данных пользователя. */
    uint32_t work_rsteps;
@@ -3789,13 +3854,10 @@ struct MDBX_commit_latency {
    /** \brief Время "по настенным часам" затраченное на чтение и поиск внутри
     *  GC для целей поддержки и обновления самой GC. */
    uint32_t self_rtime_monotonic;
-    /** \brief Монотонное время по "настенным часам" затраченное на подготовку
+    /** \brief Время ЦПУ в режиме пользователе затраченное на подготовку
     *  страниц извлекаемых из GC для целей поддержки и обновления самой GC,
     *  включая подкачку с диска. */
-    uint32_t self_xtime_monotonic;
-    /** \brief Время ЦПУ в режиме пользователе затраченное на чтение и поиск
-     *  внтури GC для целей поддержки и обновления самой GC. */
-    uint32_t self_rtime_cpu;
+    uint32_t self_xtime_cpu;
    /** \brief Количество итераций поиска внутри GC при выделении страниц
     *  для целей поддержки и обновления самой GC. */
    uint32_t self_rsteps;
@@ -4128,6 +4190,8 @@ typedef int(MDBX_cmp_func)(const MDBX_val *a,
 *                               by current thread. */
 LIBMDBX_API int mdbx_dbi_open(MDBX_txn *txn, const char *name,
                              MDBX_db_flags_t flags, MDBX_dbi *dbi);
+LIBMDBX_API int mdbx_dbi_open2(MDBX_txn *txn, const MDBX_val *name,
+                               MDBX_db_flags_t flags, MDBX_dbi *dbi);

 /** \deprecated Please
 * \ref avoid_custom_comparators "avoid using custom comparators" and use
@@ -4147,6 +4211,9 @@ LIBMDBX_API int mdbx_dbi_open(MDBX_txn *txn, const char *name,
 MDBX_DEPRECATED LIBMDBX_API int
 mdbx_dbi_open_ex(MDBX_txn *txn, const char *name, MDBX_db_flags_t flags,
                 MDBX_dbi *dbi, MDBX_cmp_func *keycmp, MDBX_cmp_func *datacmp);
+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);

 /** \defgroup value2key Value-to-Key functions
 * \brief Value-to-Key functions to
@@ -5222,7 +5289,7 @@ mdbx_get_datacmp(MDBX_db_flags_t flags);
 * \param [in] thread         The reader thread ID.
 * \param [in] bytes_used     The number of last used page
 *                            in the MVCC-snapshot which being read,
- *                            i.e. database file can't shrinked beyond this.
+ *                            i.e. database file can't be shrunk beyond this.
 * \param [in] bytes_retained The total size of the database pages that were
 *                            retired by committed write transactions after
 *                            the reader's MVCC-snapshot,
@@ -5444,18 +5511,20 @@ typedef enum MDBX_page_type_t MDBX_page_type_t;
 #endif

 /** \brief Pseudo-name for MainDB */
-#define MDBX_PGWALK_MAIN ((const char *)((ptrdiff_t)0))
+#define MDBX_PGWALK_MAIN ((void *)((ptrdiff_t)0))
 /** \brief Pseudo-name for GarbageCollectorDB */
-#define MDBX_PGWALK_GC ((const char *)((ptrdiff_t)-1))
+#define MDBX_PGWALK_GC ((void *)((ptrdiff_t)-1))
 /** \brief Pseudo-name for MetaPages */
-#define MDBX_PGWALK_META ((const char *)((ptrdiff_t)-2))
+#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 char *const dbi, 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;
+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,
@@ -5466,13 +5535,20 @@ LIBMDBX_API int mdbx_env_pgwalk(MDBX_txn *txn, MDBX_pgvisitor_func *visitor,
 *
 * This function mostly of internal API for `mdbx_chk` utility and subject to
 * change at any time. Do not use this function to avoid shooting your own
- * leg(s). */
+ * leg(s).
+ *
+ * \note On Windows the \ref mdbx_env_open_for_recoveryW() is recommended
+ * to use. */
 LIBMDBX_API int mdbx_env_open_for_recovery(MDBX_env *env, const char *pathname,
                                           unsigned target_meta,
                                           bool writeable);
-#if defined(_WIN32) || defined(_WIN64)
+
+#if defined(_WIN32) || defined(_WIN64) || defined(DOXYGEN)
+/** \copydoc mdbx_env_open_for_recovery()
+ * \note Available only on Windows.
+ * \see mdbx_env_open_for_recovery() */
 LIBMDBX_API int mdbx_env_open_for_recoveryW(MDBX_env *env,
-                                            const wchar_t *pathnameW,
+                                            const wchar_t *pathname,
                                            unsigned target_meta,
                                            bool writeable);
 #endif /* Windows */
--- a/mdbx.h++
+++ b/mdbx.h++
@@ -1,7 +1,7 @@
 /// \file mdbx.h++
 /// \brief The libmdbx C++ API header file.
 ///
-/// \author Copyright (c) 2020-2022, Leonid Yuriev <leo@yuriev.ru>.
+/// \author Copyright (c) 2020-2023, Leonid Yuriev <leo@yuriev.ru>.
 /// \copyright SPDX-License-Identifier: Apache-2.0
 ///
 /// Tested with:
@@ -84,6 +84,11 @@
 #include <experimental/filesystem>
 #endif

+#if __cplusplus >= 201103L
+#include <chrono>
+#include <ratio>
+#endif
+
 #include "mdbx.h"

 #if (defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L) ||          \
@@ -223,17 +228,18 @@
 #endif /* MDBX_CXX20_UNLIKELY */

 #ifndef MDBX_HAVE_CXX20_CONCEPTS
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_concepts) && __cpp_lib_concepts >= 202002L)
+#if defined(__cpp_lib_concepts) && __cpp_lib_concepts >= 202002L
 #include <concepts>
 #define MDBX_HAVE_CXX20_CONCEPTS 1
+#elif defined(DOXYGEN)
+#define MDBX_HAVE_CXX20_CONCEPTS 1
 #else
 #define MDBX_HAVE_CXX20_CONCEPTS 0
 #endif /* <concepts> */
 #endif /* MDBX_HAVE_CXX20_CONCEPTS */

 #ifndef MDBX_CXX20_CONCEPT
-#if MDBX_HAVE_CXX20_CONCEPTS
+#if MDBX_HAVE_CXX20_CONCEPTS || defined(DOXYGEN)
 #define MDBX_CXX20_CONCEPT(CONCEPT, NAME) CONCEPT NAME
 #else
 #define MDBX_CXX20_CONCEPT(CONCEPT, NAME) typename NAME
@@ -241,7 +247,7 @@
 #endif /* MDBX_CXX20_CONCEPT */

 #ifndef MDBX_ASSERT_CXX20_CONCEPT_SATISFIED
-#if MDBX_HAVE_CXX20_CONCEPTS
+#if MDBX_HAVE_CXX20_CONCEPTS || defined(DOXYGEN)
 #define MDBX_ASSERT_CXX20_CONCEPT_SATISFIED(CONCEPT, TYPE)                     \
  static_assert(CONCEPT<TYPE>)
 #else
@@ -287,7 +293,7 @@ namespace mdbx {
 // To enable all kinds of an compiler optimizations we use a byte-like type
 // that don't presumes aliases for pointers as does the `char` type and its
 // derivatives/typedefs.
-// Please see https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/263
+// Please see https://libmdbx.dqdkfa.ru/dead-github/issues/263
 // for reasoning of the use of `char8_t` type and switching to `__restrict__`.
 using byte = char8_t;
 #else
@@ -385,6 +391,11 @@ using path = ::std::wstring;
 using path = ::std::string;
 #endif /* mdbx::path */

+#if __cplusplus >= 201103L || defined(DOXYGEN)
+/// \brief Duration in 1/65536 units of second.
+using duration = ::std::chrono::duration<unsigned, ::std::ratio<1, 65536>>;
+#endif /* Duration for C++11 */
+
 /// \defgroup cxx_exceptions exceptions and errors
 /// @{

@@ -551,8 +562,11 @@ static MDBX_CXX14_CONSTEXPR size_t check_length(size_t headroom, size_t payload,
 /// \defgroup cxx_data slices and buffers
 /// @{

-#if MDBX_HAVE_CXX20_CONCEPTS
+#if MDBX_HAVE_CXX20_CONCEPTS || defined(DOXYGEN)

+/** \concept MutableByteProducer
+ *  \interface MutableByteProducer
+ *  \brief MutableByteProducer C++20 concept */
 template <typename T>
 concept MutableByteProducer = requires(T a, char array[42]) {
  { a.is_empty() } -> std::same_as<bool>;
@@ -560,6 +574,9 @@ concept MutableByteProducer = requires(T a, char array[42]) {
  { a.write_bytes(&array[0], size_t(42)) } -> std::same_as<char *>;
 };

+/** \concept ImmutableByteProducer
+ *  \interface ImmutableByteProducer
+ *  \brief ImmutableByteProducer C++20 concept */
 template <typename T>
 concept ImmutableByteProducer = requires(const T &a, char array[42]) {
  { a.is_empty() } -> std::same_as<bool>;
@@ -567,6 +584,9 @@ concept ImmutableByteProducer = requires(const T &a, char array[42]) {
  { a.write_bytes(&array[0], size_t(42)) } -> std::same_as<char *>;
 };

+/** \concept SliceTranscoder
+ *  \interface SliceTranscoder
+ *  \brief SliceTranscoder C++20 concept */
 template <typename T>
 concept SliceTranscoder = ImmutableByteProducer<T> &&
    requires(const slice &source, const T &a) {
@@ -2639,7 +2659,7 @@ public:
    return buffer(src, make_reference);
  }

-  static buffer key_from(const silo &&src) noexcept {
+  static buffer key_from(silo &&src) noexcept {
    return buffer(::std::move(src));
  }

@@ -3106,10 +3126,12 @@ public:
    operate_parameters(const operate_parameters &) noexcept = default;
    MDBX_CXX14_CONSTEXPR operate_parameters &
    operator=(const operate_parameters &) noexcept = default;
-    MDBX_env_flags_t
-    make_flags(bool accede = true, ///< \copydoc MDBX_ACCEDE
-               bool use_subdirectory =
-                   false ///< use subdirectory to place the DB files
+    MDBX_env_flags_t make_flags(
+        bool accede = true, ///< Allows accepting incompatible operating options
+                            ///< in case the database is already being used by
+                            ///< another process(es) \see MDBX_ACCEDE
+        bool use_subdirectory =
+            false ///< use subdirectory to place the DB files
    ) const;
    static env::mode mode_from_flags(MDBX_env_flags_t) noexcept;
    static env::durability durability_from_flags(MDBX_env_flags_t) noexcept;
@@ -3334,9 +3356,11 @@ public:

  /// \brief Returns the maximum number of threads/reader slots for the
  /// environment.
+  /// \see extra_runtime_option::max_readers
  inline unsigned max_readers() const;

  /// \brief Returns the maximum number of named databases for the environment.
+  /// \see extra_runtime_option::max_maps
  inline unsigned max_maps() const;

  /// \brief Returns the application context associated with the environment.
@@ -3348,59 +3372,117 @@ public:
  /// \brief Sets threshold to force flush the data buffers to disk, for
  /// non-sync durability modes.
  ///
-  /// The threshold value affects all processes which operates with given
-  /// environment until the last process close environment or a new value will
-  /// be settled.
-  /// Data is always written to disk when \ref txn_managed::commit() is called,
-  /// but the operating system may keep it buffered. MDBX always flushes the OS
-  /// buffers upon commit as well, unless the environment was opened with \ref
-  /// whole_fragile, \ref lazy_weak_tail or in part \ref
-  /// half_synchronous_weak_last. The default is 0, than mean no any threshold
-  /// checked, and no additional flush will be made.
+  /// \details The threshold value affects all processes which operates with
+  /// given environment until the last process close environment or a new value
+  /// will be settled. Data is always written to disk when \ref
+  /// txn_managed::commit() is called, but the operating system may keep it
+  /// buffered. MDBX always flushes the OS buffers upon commit as well, unless
+  /// the environment was opened with \ref whole_fragile, \ref lazy_weak_tail or
+  /// in part \ref half_synchronous_weak_last.
  ///
+  /// The default is 0, than mean no any threshold checked, and no additional
+  /// flush will be made.
+  /// \see extra_runtime_option::sync_bytes
  inline env &set_sync_threshold(size_t bytes);

+  /// \brief Gets threshold used to force flush the data buffers to disk, for
+  /// non-sync durability modes.
+  ///
+  /// \copydetails set_sync_threshold()
+  /// \see extra_runtime_option::sync_bytes
+  inline size_t sync_threshold() const;
+
+#if __cplusplus >= 201103L || defined(DOXYGEN)
  /// \brief Sets relative period since the last unsteady commit to force flush
  /// the data buffers to disk, for non-sync durability modes.
  ///
-  /// The relative period value affects all processes which operates with given
-  /// environment until the last process close environment or a new value will
-  /// be settled.
-  /// Data is always written to disk when \ref txn_managed::commit() is called,
-  /// but the operating system may keep it buffered. MDBX always flushes the OS
-  /// buffers upon commit as well, unless the environment was opened with \ref
-  /// whole_fragile, \ref lazy_weak_tail or in part \ref
-  /// half_synchronous_weak_last. Settled period don't checked asynchronously,
-  /// but only by the \ref txn_managed::commit() and \ref env::sync_to_disk()
-  /// functions. Therefore, in cases where transactions are committed
-  /// infrequently and/or irregularly, polling by \ref env::poll_sync_to_disk()
-  /// may be a reasonable solution to timeout enforcement. The default is 0,
-  /// than mean no any timeout checked, and no additional flush will be made.
+  /// \details The relative period value affects all processes which operates
+  /// with given environment until the last process close environment or a new
+  /// value will be settled. Data is always written to disk when \ref
+  /// txn_managed::commit() is called, but the operating system may keep it
+  /// buffered. MDBX always flushes the OS buffers upon commit as well, unless
+  /// the environment was opened with \ref whole_fragile, \ref lazy_weak_tail or
+  /// in part \ref half_synchronous_weak_last. Settled period don't checked
+  /// asynchronously, but only by the \ref txn_managed::commit() and \ref
+  /// env::sync_to_disk() functions. Therefore, in cases where transactions are
+  /// committed infrequently and/or irregularly, polling by \ref
+  /// env::poll_sync_to_disk() may be a reasonable solution to timeout
+  /// enforcement.
  ///
+  /// The default is 0, than mean no any timeout checked, and no additional
+  /// flush will be made.
+  /// \see extra_runtime_option::sync_period
+  inline env &set_sync_period(const duration &period);
+
+  /// \brief Gets relative period since the last unsteady commit that used to
+  /// force flush the data buffers to disk, for non-sync durability modes.
+  /// \copydetails set_sync_period(const duration&)
+  /// \see set_sync_period(const duration&)
+  /// \see extra_runtime_option::sync_period
+  inline duration sync_period() const;
+#endif
+
+  /// \copydoc set_sync_period(const duration&)
  /// \param [in] seconds_16dot16  The period in 1/65536 of second when a
  /// synchronous flush would be made since the last unsteady commit.
-  inline env &set_sync_period(unsigned seconds_16dot16);
+  inline env &set_sync_period__seconds_16dot16(unsigned seconds_16dot16);

-  /// \brief Sets relative period since the last unsteady commit to force flush
-  /// the data buffers to disk, for non-sync durability modes.
-  ///
-  /// The relative period value affects all processes which operates with given
-  /// environment until the last process close environment or a new value will
-  /// be settled.
-  /// Data is always written to disk when \ref txn_managed::commit() is called,
-  /// but the operating system may keep it buffered. MDBX always flushes the OS
-  /// buffers upon commit as well, unless the environment was opened with \ref
-  /// whole_fragile, \ref lazy_weak_tail or in part \ref
-  /// half_synchronous_weak_last. Settled period don't checked asynchronously,
-  /// but only by the \ref txn_managed::commit() and \ref env::sync_to_disk()
-  /// functions. Therefore, in cases where transactions are committed
-  /// infrequently and/or irregularly, polling by \ref env::poll_sync_to_disk()
-  /// may be a reasonable solution to timeout enforcement. The default is 0,
-  /// than mean no any timeout checked, and no additional flush will be made.
-  ///
+  /// \copydoc sync_period()
+  /// \see sync_period__seconds_16dot16(unsigned)
+  inline unsigned sync_period__seconds_16dot16() const;
+
+  /// \copydoc set_sync_period(const duration&)
  /// \param [in] seconds  The period in second when a synchronous flush would
  /// be made since the last unsteady commit.
-  inline env &set_sync_period(double seconds);
+  inline env &set_sync_period__seconds_double(double seconds);
+
+  /// \copydoc sync_period()
+  /// \see set_sync_period__seconds_double(double)
+  inline double sync_period__seconds_double() const;
+
+  /// \copydoc MDBX_option_t
+  enum class extra_runtime_option {
+    /// \copydoc MDBX_opt_max_db
+    /// \see max_maps() \see env::operate_parameters::max_maps
+    max_maps = MDBX_opt_max_db,
+    /// \copydoc MDBX_opt_max_readers
+    /// \see max_readers() \see env::operate_parameters::max_readers
+    max_readers = MDBX_opt_max_readers,
+    /// \copydoc MDBX_opt_sync_bytes
+    /// \see sync_threshold() \see set_sync_threshold()
+    sync_bytes = MDBX_opt_sync_bytes,
+    /// \copydoc MDBX_opt_sync_period
+    /// \see sync_period() \see set_sync_period()
+    sync_period = MDBX_opt_sync_period,
+    /// \copydoc MDBX_opt_rp_augment_limit
+    rp_augment_limit = MDBX_opt_rp_augment_limit,
+    /// \copydoc MDBX_opt_loose_limit
+    loose_limit = MDBX_opt_loose_limit,
+    /// \copydoc MDBX_opt_dp_reserve_limit
+    dp_reserve_limit = MDBX_opt_dp_reserve_limit,
+    /// \copydoc MDBX_opt_txn_dp_limit
+    dp_limit = MDBX_opt_txn_dp_limit,
+    /// \copydoc MDBX_opt_txn_dp_initial
+    dp_initial = MDBX_opt_txn_dp_initial,
+    /// \copydoc MDBX_opt_spill_max_denominator
+    spill_max_denominator = MDBX_opt_spill_max_denominator,
+    /// \copydoc MDBX_opt_spill_min_denominator
+    spill_min_denominator = MDBX_opt_spill_min_denominator,
+    /// \copydoc MDBX_opt_spill_parent4child_denominator
+    spill_parent4child_denominator = MDBX_opt_spill_parent4child_denominator,
+    /// \copydoc MDBX_opt_merge_threshold_16dot16_percent
+    merge_threshold_16dot16_percent = MDBX_opt_merge_threshold_16dot16_percent,
+    /// \copydoc MDBX_opt_writethrough_threshold
+    writethrough_threshold = MDBX_opt_writethrough_threshold,
+    /// \copydoc MDBX_opt_prefault_write_enable
+    prefault_write_enable = MDBX_opt_prefault_write_enable,
+  };
+
+  /// \copybrief mdbx_env_set_option()
+  inline env &set_extra_option(extra_runtime_option option, uint64_t value);
+
+  /// \copybrief mdbx_env_get_option()
+  inline uint64_t extra_option(extra_runtime_option option) const;

  /// \brief Alter environment flags.
  inline env &alter_flags(MDBX_env_flags_t flags, bool on_off);
@@ -3450,7 +3532,7 @@ public:
                              /// transactions since the current read
                              /// transaction started.
    size_t bytes_used; ///< The number of last used page in the MVCC-snapshot
-                       ///< which being read, i.e. database file can't shrinked
+                       ///< which being read, i.e. database file can't be shrunk
                       ///< beyond this.
    size_t bytes_retained; ///< The total size of the database pages that
                           ///< were retired by committed write transactions
@@ -3591,7 +3673,7 @@ public:
  void close(bool dont_sync = false);

  env_managed(env_managed &&) = default;
-  env_managed &operator=(env_managed &&other) {
+  env_managed &operator=(env_managed &&other) noexcept {
    if (MDBX_UNLIKELY(handle_))
      MDBX_CXX20_UNLIKELY {
        assert(handle_ != other.handle_);
@@ -3890,7 +3972,7 @@ class LIBMDBX_API_TYPE txn_managed : public txn {
 public:
  MDBX_CXX11_CONSTEXPR txn_managed() noexcept = default;
  txn_managed(txn_managed &&) = default;
-  txn_managed &operator=(txn_managed &&other) {
+  txn_managed &operator=(txn_managed &&other) noexcept {
    if (MDBX_UNLIKELY(handle_))
      MDBX_CXX20_UNLIKELY {
        assert(handle_ != other.handle_);
@@ -4112,7 +4194,7 @@ public:
  void close();

  cursor_managed(cursor_managed &&) = default;
-  cursor_managed &operator=(cursor_managed &&other) {
+  cursor_managed &operator=(cursor_managed &&other) noexcept {
    if (MDBX_UNLIKELY(handle_))
      MDBX_CXX20_UNLIKELY {
        assert(handle_ != other.handle_);
@@ -5056,13 +5138,53 @@ inline env &env::set_sync_threshold(size_t bytes) {
  return *this;
 }

-inline env &env::set_sync_period(unsigned seconds_16dot16) {
+inline size_t env::sync_threshold() const {
+  size_t bytes;
+  error::success_or_throw(::mdbx_env_get_syncbytes(handle_, &bytes));
+  return bytes;
+}
+
+inline env &env::set_sync_period__seconds_16dot16(unsigned seconds_16dot16) {
  error::success_or_throw(::mdbx_env_set_syncperiod(handle_, seconds_16dot16));
  return *this;
 }

-inline env &env::set_sync_period(double seconds) {
-  return set_sync_period(unsigned(seconds * 65536));
+inline unsigned env::sync_period__seconds_16dot16() const {
+  unsigned seconds_16dot16;
+  error::success_or_throw(::mdbx_env_get_syncperiod(handle_, &seconds_16dot16));
+  return seconds_16dot16;
+}
+
+inline env &env::set_sync_period__seconds_double(double seconds) {
+  return set_sync_period__seconds_16dot16(unsigned(seconds * 65536));
+}
+
+inline double env::sync_period__seconds_double() const {
+  return sync_period__seconds_16dot16() / 65536.0;
+}
+
+#if __cplusplus >= 201103L
+inline env &env::set_sync_period(const duration &period) {
+  return set_sync_period__seconds_16dot16(period.count());
+}
+
+inline duration env::sync_period() const {
+  return duration(sync_period__seconds_16dot16());
+}
+#endif
+
+inline env &env::set_extra_option(enum env::extra_runtime_option option,
+                                  uint64_t value) {
+  error::success_or_throw(
+      ::mdbx_env_set_option(handle_, ::MDBX_option_t(option), value));
+  return *this;
+}
+
+inline uint64_t env::extra_option(enum env::extra_runtime_option option) const {
+  uint64_t value;
+  error::success_or_throw(
+      ::mdbx_env_get_option(handle_, ::MDBX_option_t(option), &value));
+  return value;
 }

 inline env &env::alter_flags(MDBX_env_flags_t flags, bool on_off) {
--- a/src/alloy.c
+++ b/src/alloy.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/src/base.h
+++ b/src/base.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -293,8 +293,8 @@ __extern_C key_t ftok(const char *, int);
 /* Byteorder */

 #if defined(i386) || defined(__386) || defined(__i386) || defined(__i386__) || \
-    defined(i486) || defined(__i486) || defined(__i486__) ||                   \
-    defined(i586) | defined(__i586) || defined(__i586__) || defined(i686) ||   \
+    defined(i486) || defined(__i486) || defined(__i486__) || defined(i586) ||  \
+    defined(__i586) || defined(__i586__) || defined(i686) ||                   \
    defined(__i686) || defined(__i686__) || defined(_M_IX86) ||                \
    defined(_X86_) || defined(__THW_INTEL__) || defined(__I86__) ||            \
    defined(__INTEL__) || defined(__x86_64) || defined(__x86_64__) ||          \
@@ -572,17 +572,13 @@ __extern_C key_t ftok(const char *, int);

 #ifndef __hot
 #if defined(__OPTIMIZE__)
-#if defined(__e2k__)
-#define __hot __attribute__((__hot__)) __optimize(3)
-#elif defined(__clang__) && !__has_attribute(__hot_) &&                        \
+#if defined(__clang__) && !__has_attribute(__hot__) &&                         \
    __has_attribute(__section__) &&                                            \
    (defined(__linux__) || defined(__gnu_linux__))
 /* just put frequently used functions in separate section */
 #define __hot __attribute__((__section__("text.hot"))) __optimize("O3")
-#elif defined(__LCC__)
-#define __hot __attribute__((__hot__, __optimize__("Ofast,O4")))
 #elif defined(__GNUC__) || __has_attribute(__hot__)
-#define __hot __attribute__((__hot__)) __optimize("O3")
+#define __hot __attribute__((__hot__))
 #else
 #define __hot __optimize("O3")
 #endif
@@ -593,17 +589,13 @@ __extern_C key_t ftok(const char *, int);

 #ifndef __cold
 #if defined(__OPTIMIZE__)
-#if defined(__e2k__)
-#define __cold __attribute__((__cold__)) __optimize(1)
-#elif defined(__clang__) && !__has_attribute(cold) &&                          \
+#if defined(__clang__) && !__has_attribute(__cold__) &&                        \
    __has_attribute(__section__) &&                                            \
    (defined(__linux__) || defined(__gnu_linux__))
 /* just put infrequently used functions in separate section */
 #define __cold __attribute__((__section__("text.unlikely"))) __optimize("Os")
-#elif defined(__LCC__)
-#define __hot __attribute__((__cold__, __optimize__("Osize")))
-#elif defined(__GNUC__) || __has_attribute(cold)
-#define __cold __attribute__((__cold__)) __optimize("Os")
+#elif defined(__GNUC__) || __has_attribute(__cold__)
+#define __cold __attribute__((__cold__))
 #else
 #define __cold __optimize("Os")
 #endif
@@ -669,6 +661,28 @@ __extern_C key_t ftok(const char *, int);
 #endif
 #endif /* MDBX_WEAK_IMPORT_ATTRIBUTE */

+#ifndef MDBX_GOOFY_MSVC_STATIC_ANALYZER
+#ifdef _PREFAST_
+#define MDBX_GOOFY_MSVC_STATIC_ANALYZER 1
+#else
+#define MDBX_GOOFY_MSVC_STATIC_ANALYZER 0
+#endif
+#endif /* MDBX_GOOFY_MSVC_STATIC_ANALYZER */
+
+#if MDBX_GOOFY_MSVC_STATIC_ANALYZER || (defined(_MSC_VER) && _MSC_VER > 1919)
+#define MDBX_ANALYSIS_ASSUME(expr) __analysis_assume(expr)
+#ifdef _PREFAST_
+#define MDBX_SUPPRESS_GOOFY_MSVC_ANALYZER(warn_id)                             \
+  __pragma(prefast(suppress : warn_id))
+#else
+#define MDBX_SUPPRESS_GOOFY_MSVC_ANALYZER(warn_id)                             \
+  __pragma(warning(suppress : warn_id))
+#endif
+#else
+#define MDBX_ANALYSIS_ASSUME(expr) assert(expr)
+#define MDBX_SUPPRESS_GOOFY_MSVC_ANALYZER(warn_id)
+#endif /* MDBX_GOOFY_MSVC_STATIC_ANALYZER */
+
 /*----------------------------------------------------------------------------*/

 #if defined(MDBX_USE_VALGRIND)
--- a/src/bits.md
+++ b/src/bits.md
@@ -1,12 +1,12 @@
 N |   MASK  | ENV       | TXN          | DB       | PUT       | DBI        | NODE    | PAGE     | MRESIZE |
 --|---------|-----------|--------------|----------|-----------|------------|---------|----------|---------|
-0 |0000 0001|ALLOC_CACHE|TXN_FINISHED  |          |           |DBI_DIRTY   |F_BIGDATA|P_BRANCH  |         |
-1 |0000 0002|ALLOC_GC   |TXN_ERROR     |REVERSEKEY|F_SUBDATA  |DBI_STALE   |F_SUBDATA|P_LEAF    |         |
-2 |0000 0004|ALLOC_NEW  |TXN_DIRTY     |DUPSORT   |           |DBI_FRESH   |F_DUPDATA|P_OVERFLOW|         |
-3 |0000 0008|ALLOC_SLOT |TXN_SPILLS    |INTEGERKEY|           |DBI_CREAT   |         |P_META    |         |
-4 |0000 0010|ALLOC_FAKE |TXN_HAS_CHILD |DUPFIXED  |NOOVERWRITE|DBI_VALID   |         |P_BAD     |         |
-5 |0000 0020|           |TXN_UPDATE_GC |INTEGERDUP|NODUPDATA  |DBI_USRVALID|         |P_LEAF2   |         |
-6 |0000 0040|           |TXN_FROZEN_RE |REVERSEDUP|CURRENT    |DBI_DUPDATA |         |P_SUBP    |         |
+0 |0000 0001|ALLOC_RSRV |TXN_FINISHED  |          |           |DBI_DIRTY   |F_BIGDATA|P_BRANCH  |         |
+1 |0000 0002|ALLOC_UNIMP|TXN_ERROR     |REVERSEKEY|F_SUBDATA  |DBI_STALE   |F_SUBDATA|P_LEAF    |         |
+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   |         |
+6 |0000 0040|           |              |REVERSEDUP|CURRENT    |DBI_DUPDATA |         |P_SUBP    |         |
 7 |0000 0080|           |              |          |ALLDUPS    |DBI_AUDITED |         |          |         |
 8 |0000 0100| _MAY_MOVE |              |          |           |            |         |          | <=      |
 9 |0000 0200| _MAY_UNMAP|              |          |           |            |         |          | <=      |
@@ -15,7 +15,7 @@ N |   MASK  | ENV       | TXN          | DB       | PUT       | DBI        | NOD
 12|0000 1000|           |              |          |           |            |         |          |         |
 13|0000 2000|VALIDATION |              |          |           |            |         |P_SPILLED |         |
 14|0000 4000|NOSUBDIR   |              |          |           |            |         |P_LOOSE   |         |
-15|0000 8000|           |              |DB_VALID  |NOSPILL    |            |         |P_FROZEN  |         |
+15|0000 8000|           |              |DB_VALID  |           |            |         |P_FROZEN  |         |
 16|0001 0000|SAFE_NOSYNC|TXN_NOSYNC    |          |RESERVE    |            |RESERVE  |          |         |
 17|0002 0000|RDONLY     |TXN_RDONLY    |          |APPEND     |            |APPEND   |          | <=      |
 18|0004 0000|NOMETASYNC |TXN_NOMETASYNC|CREATE    |APPENDDUP  |            |         |          |         |
--- a/src/core.c
+++ b/src/core.c
--- a/src/debug_begin.h
+++ b/src/debug_begin.h
@@ -1,42 +1,42 @@
 #if defined(__GNUC__) && !defined(__LCC__)

-#pragma push_macro("mdbx_trace")
-#pragma push_macro("mdbx_debug")
-#pragma push_macro("mdbx_verbose")
-#pragma push_macro("mdbx_notice")
-#pragma push_macro("mdbx_warning")
-#pragma push_macro("mdbx_error")
-#pragma push_macro("mdbx_assert")
+#pragma push_macro("TRACE")
+#pragma push_macro("DEBUG")
+#pragma push_macro("VERBOSE")
+#pragma push_macro("NOTICE")
+#pragma push_macro("WARNING")
+#pragma push_macro("ERROR")
+#pragma push_macro("eASSERT")

-#undef mdbx_trace
-#define mdbx_trace(fmt, ...)                                                   \
-  mdbx_debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n", __VA_ARGS__)
+#undef TRACE
+#define TRACE(fmt, ...)                                                        \
+  debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n", __VA_ARGS__)

-#undef mdbx_debug
-#define mdbx_debug(fmt, ...)                                                   \
-  mdbx_debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n", __VA_ARGS__)
+#undef DEBUG
+#define DEBUG(fmt, ...)                                                        \
+  debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n", __VA_ARGS__)

-#undef mdbx_verbose
-#define mdbx_verbose(fmt, ...)                                                 \
-  mdbx_debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n", __VA_ARGS__)
+#undef VERBOSE
+#define VERBOSE(fmt, ...)                                                      \
+  debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n", __VA_ARGS__)

-#undef mdbx_notice
-#define mdbx_notice(fmt, ...)                                                  \
-  mdbx_debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n", __VA_ARGS__)
+#undef NOTICE
+#define NOTICE(fmt, ...)                                                       \
+  debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n", __VA_ARGS__)

-#undef mdbx_warning
-#define mdbx_warning(fmt, ...)                                                 \
-  mdbx_debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n", __VA_ARGS__)
+#undef WARNING
+#define WARNING(fmt, ...)                                                      \
+  debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n", __VA_ARGS__)

-#undef mdbx_error
-#define mdbx_error(fmt, ...)                                                   \
-  mdbx_debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n", __VA_ARGS__)
+#undef ERROR
+#define ERROR(fmt, ...)                                                        \
+  debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n", __VA_ARGS__)

-#undef mdbx_assert
-#define mdbx_assert(env, expr) mdbx_ensure(env, expr)
+#undef eASSERT
+#define eASSERT(env, expr) ENSURE(env, expr)

 #if !defined(__clang__)
-#pragma GCC optimize("-O0")
+#pragma GCC optimize("-Og")
 #endif

 #endif /* GCC only */
--- a/src/debug_end.h
+++ b/src/debug_end.h
@@ -1,12 +1,12 @@
 #if defined(__GNUC__) && !defined(__LCC__)

-#pragma pop_macro("mdbx_trace")
-#pragma pop_macro("mdbx_debug")
-#pragma pop_macro("mdbx_verbose")
-#pragma pop_macro("mdbx_notice")
-#pragma pop_macro("mdbx_warning")
-#pragma pop_macro("mdbx_error")
-#pragma pop_macro("mdbx_assert")
+#pragma pop_macro("TRACE")
+#pragma pop_macro("DEBUG")
+#pragma pop_macro("VERBOSE")
+#pragma pop_macro("NOTICE")
+#pragma pop_macro("WARNING")
+#pragma pop_macro("ERROR")
+#pragma pop_macro("eASSERT")

 #if !defined(__clang__)
 #pragma GCC reset_options
--- a/src/internals.h
+++ b/src/internals.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -35,7 +35,7 @@

 /** Disables using GNU/Linux libc extensions.
 * \ingroup build_option
- * \note This option couldn't be moved to the options.h since dependant
+ * \note This option couldn't be moved to the options.h since dependent
 * control macros/defined should be prepared before include the options.h */
 #ifndef MDBX_DISABLE_GNU_SOURCE
 #define MDBX_DISABLE_GNU_SOURCE 0
@@ -86,14 +86,18 @@
 #pragma warning(disable : 4464) /* relative include path contains '..' */
 #endif
 #if _MSC_VER > 1913
-#pragma warning(disable : 5045) /* Compiler will insert Spectre mitigation...  \
-                                 */
+#pragma warning(disable : 5045) /* will insert Spectre mitigation... */
 #endif
 #if _MSC_VER > 1914
 #pragma warning(                                                               \
    disable : 5105) /* winbase.h(9531): warning C5105: macro expansion         \
                       producing 'defined' has undefined behavior */
 #endif
+#if _MSC_VER > 1930
+#pragma warning(disable : 6235) /* <expression> is always a constant */
+#pragma warning(disable : 6237) /* <expression> is never evaluated and might   \
+                                   have side effects */
+#endif
 #pragma warning(disable : 4710) /* 'xyz': function not inlined */
 #pragma warning(disable : 4711) /* function 'xyz' selected for automatic       \
                                   inline expansion */
@@ -227,6 +231,142 @@ extern LIBMDBX_API const char *const mdbx_sourcery_anchor;
 #undef NDEBUG
 #endif

+#ifndef __cplusplus
+/*----------------------------------------------------------------------------*/
+/* Debug and Logging stuff */
+
+#define MDBX_RUNTIME_FLAGS_INIT                                                \
+  ((MDBX_DEBUG) > 0) * MDBX_DBG_ASSERT + ((MDBX_DEBUG) > 1) * MDBX_DBG_AUDIT
+
+extern uint8_t runtime_flags;
+extern uint8_t loglevel;
+extern MDBX_debug_func *debug_logger;
+
+MDBX_MAYBE_UNUSED static __inline void jitter4testing(bool tiny) {
+#if MDBX_DEBUG
+  if (MDBX_DBG_JITTER & runtime_flags)
+    osal_jitter(tiny);
+#else
+  (void)tiny;
+#endif
+}
+
+MDBX_INTERNAL_FUNC void MDBX_PRINTF_ARGS(4, 5)
+    debug_log(int level, const char *function, int line, const char *fmt, ...)
+        MDBX_PRINTF_ARGS(4, 5);
+MDBX_INTERNAL_FUNC void debug_log_va(int level, const char *function, int line,
+                                     const char *fmt, va_list args);
+
+#if MDBX_DEBUG
+#define LOG_ENABLED(msg) unlikely(msg <= loglevel)
+#define AUDIT_ENABLED() unlikely((runtime_flags & MDBX_DBG_AUDIT))
+#else /* MDBX_DEBUG */
+#define LOG_ENABLED(msg) (msg < MDBX_LOG_VERBOSE && msg <= loglevel)
+#define AUDIT_ENABLED() (0)
+#endif /* MDBX_DEBUG */
+
+#if MDBX_FORCE_ASSERTIONS
+#define ASSERT_ENABLED() (1)
+#elif MDBX_DEBUG
+#define ASSERT_ENABLED() likely((runtime_flags & MDBX_DBG_ASSERT))
+#else
+#define ASSERT_ENABLED() (0)
+#endif /* assertions */
+
+#define DEBUG_EXTRA(fmt, ...)                                                  \
+  do {                                                                         \
+    if (LOG_ENABLED(MDBX_LOG_EXTRA))                                           \
+      debug_log(MDBX_LOG_EXTRA, __func__, __LINE__, fmt, __VA_ARGS__);         \
+  } while (0)
+
+#define DEBUG_EXTRA_PRINT(fmt, ...)                                            \
+  do {                                                                         \
+    if (LOG_ENABLED(MDBX_LOG_EXTRA))                                           \
+      debug_log(MDBX_LOG_EXTRA, NULL, 0, fmt, __VA_ARGS__);                    \
+  } while (0)
+
+#define TRACE(fmt, ...)                                                        \
+  do {                                                                         \
+    if (LOG_ENABLED(MDBX_LOG_TRACE))                                           \
+      debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n", __VA_ARGS__);    \
+  } while (0)
+
+#define DEBUG(fmt, ...)                                                        \
+  do {                                                                         \
+    if (LOG_ENABLED(MDBX_LOG_DEBUG))                                           \
+      debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n", __VA_ARGS__);    \
+  } while (0)
+
+#define VERBOSE(fmt, ...)                                                      \
+  do {                                                                         \
+    if (LOG_ENABLED(MDBX_LOG_VERBOSE))                                         \
+      debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n", __VA_ARGS__);  \
+  } while (0)
+
+#define NOTICE(fmt, ...)                                                       \
+  do {                                                                         \
+    if (LOG_ENABLED(MDBX_LOG_NOTICE))                                          \
+      debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n", __VA_ARGS__);   \
+  } while (0)
+
+#define WARNING(fmt, ...)                                                      \
+  do {                                                                         \
+    if (LOG_ENABLED(MDBX_LOG_WARN))                                            \
+      debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n", __VA_ARGS__);     \
+  } while (0)
+
+#undef ERROR /* wingdi.h                                                       \
+  Yeah, morons from M$ put such definition to the public header. */
+
+#define ERROR(fmt, ...)                                                        \
+  do {                                                                         \
+    if (LOG_ENABLED(MDBX_LOG_ERROR))                                           \
+      debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n", __VA_ARGS__);    \
+  } while (0)
+
+#define FATAL(fmt, ...)                                                        \
+  debug_log(MDBX_LOG_FATAL, __func__, __LINE__, fmt "\n", __VA_ARGS__);
+
+#if MDBX_DEBUG
+#define ASSERT_FAIL(env, msg, func, line) mdbx_assert_fail(env, msg, func, line)
+#else /* MDBX_DEBUG */
+MDBX_NORETURN __cold void assert_fail(const char *msg, const char *func,
+                                      unsigned line);
+#define ASSERT_FAIL(env, msg, func, line)                                      \
+  do {                                                                         \
+    (void)(env);                                                               \
+    assert_fail(msg, func, line);                                              \
+  } while (0)
+#endif /* MDBX_DEBUG */
+
+#define ENSURE_MSG(env, expr, msg)                                             \
+  do {                                                                         \
+    if (unlikely(!(expr)))                                                     \
+      ASSERT_FAIL(env, msg, __func__, __LINE__);                               \
+  } while (0)
+
+#define ENSURE(env, expr) ENSURE_MSG(env, expr, #expr)
+
+/* assert(3) variant in environment context */
+#define eASSERT(env, expr)                                                     \
+  do {                                                                         \
+    if (ASSERT_ENABLED())                                                      \
+      ENSURE(env, expr);                                                       \
+  } while (0)
+
+/* assert(3) variant in cursor context */
+#define cASSERT(mc, expr) eASSERT((mc)->mc_txn->mt_env, expr)
+
+/* assert(3) variant in transaction context */
+#define tASSERT(txn, expr) eASSERT((txn)->mt_env, expr)
+
+#ifndef xMDBX_TOOLS /* Avoid using internal eASSERT() */
+#undef assert
+#define assert(expr) eASSERT(NULL, expr)
+#endif
+
+#endif /* __cplusplus */
+
 /*----------------------------------------------------------------------------*/
 /* Atomics */

@@ -525,16 +665,12 @@ typedef struct MDBX_meta {
 * Each non-metapage up to MDBX_meta.mm_last_pg is reachable exactly once
 * in the snapshot: Either used by a database or listed in a GC record. */
 typedef struct MDBX_page {
-  union {
 #define IS_FROZEN(txn, p) ((p)->mp_txnid < (txn)->mt_txnid)
 #define IS_SPILLED(txn, p) ((p)->mp_txnid == (txn)->mt_txnid)
 #define IS_SHADOWED(txn, p) ((p)->mp_txnid > (txn)->mt_txnid)
 #define IS_VALID(txn, p) ((p)->mp_txnid <= (txn)->mt_front)
 #define IS_MODIFIABLE(txn, p) ((p)->mp_txnid == (txn)->mt_front)
-    uint64_t
-        mp_txnid; /* txnid which created this page, maybe zero in legacy DB */
-    struct MDBX_page *mp_next; /* for in-memory list of freed pages */
-  };
+  uint64_t mp_txnid; /* txnid which created page, maybe zero in legacy DB */
  uint16_t mp_leaf2_ksize;   /* key size if this is a LEAF2 page */
 #define P_BRANCH 0x01u       /* branch page */
 #define P_LEAF 0x02u         /* leaf page */
@@ -576,18 +712,24 @@ typedef struct MDBX_page {
 /* Size of the page header, excluding dynamic data at the end */
 #define PAGEHDRSZ offsetof(MDBX_page, mp_ptrs)

+/* Pointer displacement without casting to char* to avoid pointer-aliasing */
+#define ptr_disp(ptr, disp) ((void *)(((intptr_t)(ptr)) + ((intptr_t)(disp))))
+
+/* Pointer distance as signed number of bytes */
+#define ptr_dist(more, less) (((intptr_t)(more)) - ((intptr_t)(less)))
+
+#define mp_next(mp)                                                            \
+  (*(MDBX_page **)ptr_disp((mp)->mp_ptrs, sizeof(void *) - sizeof(uint32_t)))
+
 #pragma pack(pop)

 typedef struct profgc_stat {
  /* Монотонное время по "настенным часам"
   * затраченное на чтение и поиск внутри GC */
  uint64_t rtime_monotonic;
-  /* Монотонное время по "настенным часам" затраченное
-   * на подготовку страниц извлекаемых из GC, включая подкачку с диска. */
-  uint64_t xtime_monotonic;
  /* Процессорное время в режим пользователя
-   * затраченное на чтение и поиск внутри GC */
-  uint64_t rtime_cpu;
+   * на подготовку страниц извлекаемых из GC, включая подкачку с диска. */
+  uint64_t xtime_cpu;
  /* Количество итераций чтения-поиска внутри GC при выделении страниц */
  uint32_t rsteps;
  /* Количество запросов на выделение последовательностей страниц,
@@ -617,6 +759,14 @@ typedef struct pgop_stat {
  MDBX_atomic_uint64_t
      fsync; /* Number of explicit fsync/flush-to-disk operations */

+  MDBX_atomic_uint64_t prefault; /* Number of prefault write operations */
+  MDBX_atomic_uint64_t mincore;  /* Number of mincore() calls */
+
+  MDBX_atomic_uint32_t
+      incoherence; /* number of https://libmdbx.dqdkfa.ru/dead-github/issues/269
+                      caught */
+  MDBX_atomic_uint32_t reserved;
+
  /* Статистика для профилирования GC.
   * Логически эти данные может быть стоит вынести в другую структуру,
   * но разница будет сугубо косметическая. */
@@ -756,6 +906,10 @@ typedef struct MDBX_lockinfo {

  /* Low 32-bit of txnid with which meta-pages was synced,
   * i.e. for sync-polling in the MDBX_NOMETASYNC mode. */
+#define MDBX_NOMETASYNC_LAZY_UNK (UINT32_MAX / 3)
+#define MDBX_NOMETASYNC_LAZY_FD (MDBX_NOMETASYNC_LAZY_UNK + UINT32_MAX / 8)
+#define MDBX_NOMETASYNC_LAZY_WRITEMAP                                          \
+  (MDBX_NOMETASYNC_LAZY_UNK - UINT32_MAX / 8)
  MDBX_atomic_uint32_t mti_meta_sync_txnid;

  /* Period for timed auto-sync feature, i.e. at the every steady checkpoint
@@ -770,7 +924,7 @@ typedef struct MDBX_lockinfo {

  /* Paired counter of processes that have mlock()ed part of mmapped DB.
   * The (mti_mlcnt[0] - mti_mlcnt[1]) > 0 means at least one process
-   * lock at leat one page, so therefore madvise() could return EINVAL. */
+   * lock at least one page, so therefore madvise() could return EINVAL. */
  MDBX_atomic_uint32_t mti_mlcnt[2];

  MDBX_ALIGNAS(MDBX_CACHELINE_SIZE) /* cacheline ----------------------------*/
@@ -805,6 +959,12 @@ typedef struct MDBX_lockinfo {
  /* Shared anchor for tracking readahead edge and enabled/disabled status. */
  pgno_t mti_readahead_anchor;

+  /* Shared cache for mincore() results */
+  struct {
+    pgno_t begin[4];
+    uint64_t mask[4];
+  } mti_mincore_cache;
+
  MDBX_ALIGNAS(MDBX_CACHELINE_SIZE) /* cacheline ----------------------------*/

  /* Readeaders registration lock. */
@@ -877,7 +1037,8 @@ typedef struct MDBX_lockinfo {
 #endif /* MDBX_WORDBITS */

 #define MDBX_READERS_LIMIT 32767
-#define MDBX_RADIXSORT_THRESHOLD 333
+#define MDBX_RADIXSORT_THRESHOLD 142
+#define MDBX_GOLD_RATIO_DBL 1.6180339887498948482

 /*----------------------------------------------------------------------------*/

@@ -902,14 +1063,7 @@ typedef txnid_t *MDBX_TXL;
 /* An Dirty-Page list item is an pgno/pointer pair. */
 typedef struct MDBX_dp {
  MDBX_page *ptr;
-  pgno_t pgno;
-  union {
-    uint32_t extra;
-    __anonymous_struct_extension__ struct {
-      unsigned multi : 1;
-      unsigned lru : 31;
-    };
-  };
+  pgno_t pgno, npages;
 } MDBX_dp;

 /* An DPL (dirty-page list) is a sorted array of MDBX_DPs. */
@@ -925,7 +1079,8 @@ typedef struct MDBX_dpl {
 } MDBX_dpl;

 /* PNL sizes */
-#define MDBX_PNL_GRANULATE 1024
+#define MDBX_PNL_GRANULATE_LOG2 10
+#define MDBX_PNL_GRANULATE (1 << MDBX_PNL_GRANULATE_LOG2)
 #define MDBX_PNL_INITIAL                                                       \
  (MDBX_PNL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(pgno_t))

@@ -933,7 +1088,7 @@ typedef struct MDBX_dpl {
 #define MDBX_TXL_INITIAL                                                       \
  (MDBX_TXL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
 #define MDBX_TXL_MAX                                                           \
-  ((1u << 17) - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
+  ((1u << 26) - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))

 #define MDBX_PNL_ALLOCLEN(pl) ((pl)[-1])
 #define MDBX_PNL_GETSIZE(pl) ((size_t)((pl)[0]))
@@ -949,9 +1104,11 @@ typedef struct MDBX_dpl {
 #define MDBX_PNL_END(pl) (&(pl)[MDBX_PNL_GETSIZE(pl) + 1])

 #if MDBX_PNL_ASCENDING
+#define MDBX_PNL_EDGE(pl) ((pl) + 1)
 #define MDBX_PNL_LEAST(pl) MDBX_PNL_FIRST(pl)
 #define MDBX_PNL_MOST(pl) MDBX_PNL_LAST(pl)
 #else
+#define MDBX_PNL_EDGE(pl) ((pl) + MDBX_PNL_GETSIZE(pl))
 #define MDBX_PNL_LEAST(pl) MDBX_PNL_LAST(pl)
 #define MDBX_PNL_MOST(pl) MDBX_PNL_FIRST(pl)
 #endif
@@ -1000,13 +1157,11 @@ struct MDBX_txn {
  /* Additional flag for sync_locked() */
 #define MDBX_SHRINK_ALLOWED UINT32_C(0x40000000)

-#define MDBX_TXN_UPDATE_GC 0x20 /* GC is being updated */
-#define MDBX_TXN_FROZEN_RE 0x40 /* list of reclaimed-pgno must not altered */
+#define MDBX_TXN_DRAINED_GC 0x20 /* GC was depleted up to oldest reader */

 #define TXN_FLAGS                                                              \
  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_DIRTY | MDBX_TXN_SPILLS |     \
-   MDBX_TXN_HAS_CHILD | MDBX_TXN_INVALID | MDBX_TXN_UPDATE_GC |                \
-   MDBX_TXN_FROZEN_RE)
+   MDBX_TXN_HAS_CHILD | MDBX_TXN_INVALID | MDBX_TXN_DRAINED_GC)

 #if (TXN_FLAGS & (MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS)) ||       \
    ((MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS | TXN_FLAGS) &         \
@@ -1065,7 +1220,7 @@ struct MDBX_txn {
    struct {
      meta_troika_t troika;
      /* In write txns, array of cursors for each DB */
-      pgno_t *relist;         /* Reclaimed GC pages */
+      MDBX_PNL relist;        /* Reclaimed GC pages */
      txnid_t last_reclaimed; /* ID of last used record */
 #if MDBX_ENABLE_REFUND
      pgno_t loose_refund_wl /* FIXME: describe */;
@@ -1088,11 +1243,17 @@ struct MDBX_txn {
      MDBX_page *loose_pages;
      /* Number of loose pages (tw.loose_pages) */
      size_t loose_count;
-      size_t spill_least_removed;
-      /* 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 spill_pages;
+      union {
+        struct {
+          size_t least_removed;
+          /* 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;
+        } spilled;
+        size_t writemap_dirty_npages;
+        size_t writemap_spilled_npages;
+      };
    } tw;
  };
 };
@@ -1142,6 +1303,9 @@ struct MDBX_cursor {
 #define C_SUB 0x04         /* Cursor is a sub-cursor */
 #define C_DEL 0x08         /* last op was a cursor_del */
 #define C_UNTRACK 0x10     /* Un-track cursor when closing */
+#define C_GCU                                                                                  \
+  0x20 /* Происходит подготовка к обновлению GC, поэтому \
+        * можно брать страницы из GC даже для FREE_DBI */
  uint8_t mc_flags;

  /* Cursor checking flags. */
@@ -1200,12 +1364,12 @@ struct MDBX_env {
 #define ENV_INTERNAL_FLAGS (MDBX_FATAL_ERROR | MDBX_ENV_ACTIVE | MDBX_ENV_TXKEY)
  uint32_t me_flags;
  osal_mmap_t me_dxb_mmap; /* The main data file */
-#define me_map me_dxb_mmap.dxb
+#define me_map me_dxb_mmap.base
 #define me_lazy_fd me_dxb_mmap.fd
-#define me_fd4data me_ioring.fd
  mdbx_filehandle_t me_dsync_fd, me_fd4meta;
 #if defined(_WIN32) || defined(_WIN64)
-  HANDLE me_overlapped_fd, me_data_lock_event;
+#define me_overlapped_fd me_ioring.overlapped_fd
+  HANDLE me_data_lock_event;
 #endif                     /* Windows */
  osal_mmap_t me_lck_mmap; /* The lock file */
 #define me_lfd me_lck_mmap.fd
@@ -1233,10 +1397,12 @@ struct MDBX_env {
  uint16_t *me_dbflags;             /* array of flags from MDBX_db.md_flags */
  MDBX_atomic_uint32_t *me_dbiseqs; /* array of dbi sequence numbers */
  unsigned
-      me_maxgc_ov1page;    /* Number of pgno_t fit in a single overflow page */
-  uint32_t me_live_reader; /* have liveness lock in reader table */
-  void *me_userctx;        /* User-settable context */
+      me_maxgc_ov1page; /* Number of pgno_t fit in a single overflow page */
+  unsigned me_maxgc_per_branch;
+  uint32_t me_live_reader;        /* have liveness lock in reader table */
+  void *me_userctx;               /* User-settable context */
  MDBX_hsr_func *me_hsr_callback; /* Callback for kicking laggard readers */
+  size_t me_madv_threshold;

  struct {
    unsigned dp_reserve_limit;
@@ -1248,11 +1414,17 @@ struct MDBX_env {
    uint8_t spill_min_denominator;
    uint8_t spill_parent4child_denominator;
    unsigned merge_threshold_16dot16_percent;
+#if !(defined(_WIN32) || defined(_WIN64))
+    unsigned writethrough_threshold;
+#endif /* Windows */
+    bool prefault_write;
    union {
      unsigned all;
      /* tracks options with non-auto values but tuned by user */
      struct {
        unsigned dp_limit : 1;
+        unsigned rp_augment_limit : 1;
+        unsigned prefault_write : 1;
      } non_auto;
    } flags;
  } me_options;
@@ -1274,6 +1446,7 @@ struct MDBX_env {
    int semid;
  } me_sysv_ipc;
 #endif /* MDBX_LOCKING == MDBX_LOCKING_SYSV */
+  bool me_incore;

  MDBX_env *me_lcklist_next;

@@ -1282,6 +1455,7 @@ struct MDBX_env {
  MDBX_txn *me_txn; /* current write transaction */
  osal_fastmutex_t me_dbi_lock;
  MDBX_dbi 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;
@@ -1293,6 +1467,8 @@ struct MDBX_env {
  osal_srwlock_t me_remap_guard;
  /* Workaround for LockFileEx and WriteFile multithread bug */
  CRITICAL_SECTION me_windowsbug_lock;
+  char *me_pathname_char; /* cache of multi-byte representation of pathname
+                             to the DB files */
 #else
  osal_fastmutex_t me_remap_guard;
 #endif
@@ -1323,139 +1499,6 @@ struct MDBX_env {
 };

 #ifndef __cplusplus
-/*----------------------------------------------------------------------------*/
-/* Debug and Logging stuff */
-
-#define MDBX_RUNTIME_FLAGS_INIT                                                \
-  ((MDBX_DEBUG) > 0) * MDBX_DBG_ASSERT + ((MDBX_DEBUG) > 1) * MDBX_DBG_AUDIT
-
-extern uint8_t runtime_flags;
-extern uint8_t loglevel;
-extern MDBX_debug_func *debug_logger;
-
-MDBX_MAYBE_UNUSED static __inline void jitter4testing(bool tiny) {
-#if MDBX_DEBUG
-  if (MDBX_DBG_JITTER & runtime_flags)
-    osal_jitter(tiny);
-#else
-  (void)tiny;
-#endif
-}
-
-MDBX_INTERNAL_FUNC void MDBX_PRINTF_ARGS(4, 5)
-    debug_log(int level, const char *function, int line, const char *fmt, ...)
-        MDBX_PRINTF_ARGS(4, 5);
-MDBX_INTERNAL_FUNC void debug_log_va(int level, const char *function, int line,
-                                     const char *fmt, va_list args);
-
-#if MDBX_DEBUG
-#define LOG_ENABLED(msg) unlikely(msg <= loglevel)
-#define AUDIT_ENABLED() unlikely((runtime_flags & MDBX_DBG_AUDIT))
-#else /* MDBX_DEBUG */
-#define LOG_ENABLED(msg) (msg < MDBX_LOG_VERBOSE && msg <= loglevel)
-#define AUDIT_ENABLED() (0)
-#endif /* MDBX_DEBUG */
-
-#if MDBX_FORCE_ASSERTIONS
-#define ASSERT_ENABLED() (1)
-#elif MDBX_DEBUG
-#define ASSERT_ENABLED() likely((runtime_flags & MDBX_DBG_ASSERT))
-#else
-#define ASSERT_ENABLED() (0)
-#endif /* assertions */
-
-#define DEBUG_EXTRA(fmt, ...)                                                  \
-  do {                                                                         \
-    if (LOG_ENABLED(MDBX_LOG_EXTRA))                                           \
-      debug_log(MDBX_LOG_EXTRA, __func__, __LINE__, fmt, __VA_ARGS__);         \
-  } while (0)
-
-#define DEBUG_EXTRA_PRINT(fmt, ...)                                            \
-  do {                                                                         \
-    if (LOG_ENABLED(MDBX_LOG_EXTRA))                                           \
-      debug_log(MDBX_LOG_EXTRA, NULL, 0, fmt, __VA_ARGS__);                    \
-  } while (0)
-
-#define TRACE(fmt, ...)                                                        \
-  do {                                                                         \
-    if (LOG_ENABLED(MDBX_LOG_TRACE))                                           \
-      debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n", __VA_ARGS__);    \
-  } while (0)
-
-#define DEBUG(fmt, ...)                                                        \
-  do {                                                                         \
-    if (LOG_ENABLED(MDBX_LOG_DEBUG))                                           \
-      debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n", __VA_ARGS__);    \
-  } while (0)
-
-#define VERBOSE(fmt, ...)                                                      \
-  do {                                                                         \
-    if (LOG_ENABLED(MDBX_LOG_VERBOSE))                                         \
-      debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n", __VA_ARGS__);  \
-  } while (0)
-
-#define NOTICE(fmt, ...)                                                       \
-  do {                                                                         \
-    if (LOG_ENABLED(MDBX_LOG_NOTICE))                                          \
-      debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n", __VA_ARGS__);   \
-  } while (0)
-
-#define WARNING(fmt, ...)                                                      \
-  do {                                                                         \
-    if (LOG_ENABLED(MDBX_LOG_WARN))                                            \
-      debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n", __VA_ARGS__);     \
-  } while (0)
-
-#undef ERROR /* wingdi.h                                                       \
-  Yeah, morons from M$ put such definition to the public header. */
-
-#define ERROR(fmt, ...)                                                        \
-  do {                                                                         \
-    if (LOG_ENABLED(MDBX_LOG_ERROR))                                           \
-      debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n", __VA_ARGS__);    \
-  } while (0)
-
-#define FATAL(fmt, ...)                                                        \
-  debug_log(MDBX_LOG_FATAL, __func__, __LINE__, fmt "\n", __VA_ARGS__);
-
-#if MDBX_DEBUG
-#define ASSERT_FAIL(env, msg, func, line) mdbx_assert_fail(env, msg, func, line)
-#else /* MDBX_DEBUG */
-MDBX_NORETURN __cold void assert_fail(const char *msg, const char *func,
-                                      unsigned line);
-#define ASSERT_FAIL(env, msg, func, line)                                      \
-  do {                                                                         \
-    (void)(env);                                                               \
-    assert_fail(msg, func, line);                                              \
-  } while (0)
-#endif /* MDBX_DEBUG */
-
-#define ENSURE_MSG(env, expr, msg)                                             \
-  do {                                                                         \
-    if (unlikely(!(expr)))                                                     \
-      ASSERT_FAIL(env, msg, __func__, __LINE__);                               \
-  } while (0)
-
-#define ENSURE(env, expr) ENSURE_MSG(env, expr, #expr)
-
-/* assert(3) variant in environment context */
-#define eASSERT(env, expr)                                                     \
-  do {                                                                         \
-    if (ASSERT_ENABLED())                                                      \
-      ENSURE(env, expr);                                                       \
-  } while (0)
-
-/* assert(3) variant in cursor context */
-#define cASSERT(mc, expr) eASSERT((mc)->mc_txn->mt_env, expr)
-
-/* assert(3) variant in transaction context */
-#define tASSERT(txn, expr) eASSERT((txn)->mt_env, expr)
-
-#ifndef xMDBX_TOOLS /* Avoid using internal eASSERT() */
-#undef assert
-#define assert(expr) eASSERT(NULL, expr)
-#endif
-
 /*----------------------------------------------------------------------------*/
 /* Cache coherence and mmap invalidation */

@@ -1466,7 +1509,8 @@ MDBX_NORETURN __cold void assert_fail(const char *msg, const char *func,
 #endif /* MDBX_CPU_WRITEBACK_INCOHERENT */

 MDBX_MAYBE_UNUSED static __inline void
-osal_flush_incoherent_mmap(void *addr, size_t nbytes, const intptr_t pagesize) {
+osal_flush_incoherent_mmap(const void *addr, size_t nbytes,
+                           const intptr_t pagesize) {
 #if MDBX_MMAP_INCOHERENT_FILE_WRITE
  char *const begin = (char *)(-pagesize & (intptr_t)addr);
  char *const end =
@@ -1482,7 +1526,7 @@ osal_flush_incoherent_mmap(void *addr, size_t nbytes, const intptr_t pagesize) {
 #ifdef DCACHE
  /* MIPS has cache coherency issues.
   * Note: for any nbytes >= on-chip cache size, entire is flushed. */
-  cacheflush(addr, nbytes, DCACHE);
+  cacheflush((void *)addr, nbytes, DCACHE);
 #else
 #error "Oops, cacheflush() not available"
 #endif /* DCACHE */
@@ -1641,16 +1685,7 @@ typedef struct MDBX_node {
 *                |  1, a > b
 *                \
 */
-#ifndef __e2k__
-/* LY: fast enough on most systems */
-#define CMP2INT(a, b) (((b) > (a)) ? -1 : (a) > (b))
-#else
-/* LY: more parallelable on VLIW Elbrus */
-#define CMP2INT(a, b) (((a) > (b)) - ((b) > (a)))
-#endif
-
-/* Do not spill pages to disk if txn is getting full, may fail instead */
-#define MDBX_NOSPILL 0x8000
+#define CMP2INT(a, b) (((a) != (b)) ? (((a) < (b)) ? -1 : 1) : 0)

 MDBX_MAYBE_UNUSED MDBX_NOTHROW_CONST_FUNCTION static __inline pgno_t
 int64pgno(int64_t i64) {
@@ -1662,14 +1697,14 @@ int64pgno(int64_t i64) {
 MDBX_MAYBE_UNUSED MDBX_NOTHROW_CONST_FUNCTION static __inline pgno_t
 pgno_add(size_t base, size_t augend) {
  assert(base <= MAX_PAGENO + 1 && augend < MAX_PAGENO);
-  return int64pgno(base + augend);
+  return int64pgno((int64_t)base + (int64_t)augend);
 }

 MDBX_MAYBE_UNUSED MDBX_NOTHROW_CONST_FUNCTION static __inline pgno_t
 pgno_sub(size_t base, size_t subtrahend) {
  assert(base >= MIN_PAGENO && base <= MAX_PAGENO + 1 &&
         subtrahend < MAX_PAGENO);
-  return int64pgno(base - subtrahend);
+  return int64pgno((int64_t)base - (int64_t)subtrahend);
 }

 MDBX_MAYBE_UNUSED MDBX_NOTHROW_CONST_FUNCTION static __always_inline bool
--- a/src/lck-posix.c
+++ b/src/lck-posix.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/src/lck-windows.c
+++ b/src/lck-windows.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -152,8 +152,10 @@ static __inline int flock(HANDLE fd, unsigned flags, size_t offset,

 static __inline int flock_data(const MDBX_env *env, unsigned flags,
                               size_t offset, size_t bytes) {
-  return flock_with_event(env->me_fd4data, env->me_data_lock_event, flags,
-                          offset, bytes);
+  const HANDLE fd4data =
+      env->me_overlapped_fd ? env->me_overlapped_fd : env->me_lazy_fd;
+  return flock_with_event(fd4data, env->me_data_lock_event, flags, offset,
+                          bytes);
 }

 static int funlock(mdbx_filehandle_t fd, size_t offset, size_t bytes) {
@@ -173,7 +175,7 @@ static int funlock(mdbx_filehandle_t fd, size_t offset, size_t bytes) {
 #else
 #define DXB_MAXLEN UINT32_C(0x7ff00000)
 #endif
-#define DXB_BODY (env->me_psize * NUM_METAS), DXB_MAXLEN
+#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) {
@@ -192,25 +194,35 @@ int mdbx_txn_lock(MDBX_env *env, bool dontwait) {
    }
  }

-  if (env->me_flags & MDBX_EXCLUSIVE)
+  if (env->me_flags & MDBX_EXCLUSIVE) {
+    /* Zap: Failing to release lock 'env->me_windowsbug_lock'
+     *      in function 'mdbx_txn_lock' */
+    MDBX_SUPPRESS_GOOFY_MSVC_ANALYZER(26115);
    return MDBX_SUCCESS;
+  }

-  int rc = flock_with_event(env->me_fd4data, env->me_data_lock_event,
+  const HANDLE fd4data =
+      env->me_overlapped_fd ? env->me_overlapped_fd : env->me_lazy_fd;
+  int rc = flock_with_event(fd4data, env->me_data_lock_event,
                            dontwait ? (LCK_EXCLUSIVE | LCK_DONTWAIT)
                                     : (LCK_EXCLUSIVE | LCK_WAITFOR),
                            DXB_BODY);
  if (rc == ERROR_LOCK_VIOLATION && dontwait) {
    SleepEx(0, true);
-    rc = flock_with_event(env->me_fd4data, env->me_data_lock_event,
+    rc = flock_with_event(fd4data, env->me_data_lock_event,
                          LCK_EXCLUSIVE | LCK_DONTWAIT, DXB_BODY);
    if (rc == ERROR_LOCK_VIOLATION) {
      SleepEx(0, true);
-      rc = flock_with_event(env->me_fd4data, env->me_data_lock_event,
+      rc = flock_with_event(fd4data, env->me_data_lock_event,
                            LCK_EXCLUSIVE | LCK_DONTWAIT, DXB_BODY);
    }
  }
-  if (rc == MDBX_SUCCESS)
+  if (rc == MDBX_SUCCESS) {
+    /* Zap: Failing to release lock 'env->me_windowsbug_lock'
+     *      in function 'mdbx_txn_lock' */
+    MDBX_SUPPRESS_GOOFY_MSVC_ANALYZER(26115);
    return rc;
+  }

  LeaveCriticalSection(&env->me_windowsbug_lock);
  return (!dontwait || rc != ERROR_LOCK_VIOLATION) ? rc : MDBX_BUSY;
@@ -218,7 +230,9 @@ int mdbx_txn_lock(MDBX_env *env, bool dontwait) {

 void mdbx_txn_unlock(MDBX_env *env) {
  if ((env->me_flags & MDBX_EXCLUSIVE) == 0) {
-    int err = funlock(env->me_fd4data, DXB_BODY);
+    const HANDLE fd4data =
+        env->me_overlapped_fd ? env->me_overlapped_fd : env->me_lazy_fd;
+    int err = funlock(fd4data, DXB_BODY);
    if (err != MDBX_SUCCESS)
      mdbx_panic("%s failed: err %u", __func__, err);
  }
@@ -275,17 +289,18 @@ static int suspend_and_append(mdbx_handle_array_t **array,
                              const DWORD ThreadId) {
  const unsigned limit = (*array)->limit;
  if ((*array)->count == limit) {
-    void *ptr = osal_realloc(
-        (limit > ARRAY_LENGTH((*array)->handles))
-            ? *array
-            : /* don't free initial array on the stack */ NULL,
-        sizeof(mdbx_handle_array_t) +
-            sizeof(HANDLE) * (limit * 2 - ARRAY_LENGTH((*array)->handles)));
+    mdbx_handle_array_t *const ptr =
+        osal_realloc((limit > ARRAY_LENGTH((*array)->handles))
+                         ? *array
+                         : /* don't free initial array on the stack */ NULL,
+                     sizeof(mdbx_handle_array_t) +
+                         sizeof(HANDLE) * (limit * (size_t)2 -
+                                           ARRAY_LENGTH((*array)->handles)));
    if (!ptr)
      return MDBX_ENOMEM;
    if (limit == ARRAY_LENGTH((*array)->handles))
-      memcpy(ptr, *array, sizeof(mdbx_handle_array_t));
-    *array = (mdbx_handle_array_t *)ptr;
+      *ptr = **array;
+    *array = ptr;
    (*array)->limit = limit * 2;
  }

@@ -451,18 +466,20 @@ static void lck_unlock(MDBX_env *env) {
    SetLastError(ERROR_SUCCESS);
  }

-  if (env->me_fd4data != INVALID_HANDLE_VALUE) {
+  const HANDLE fd4data =
+      env->me_overlapped_fd ? env->me_overlapped_fd : env->me_lazy_fd;
+  if (fd4data != INVALID_HANDLE_VALUE) {
    /* explicitly unlock to avoid latency for other processes (windows kernel
     * releases such locks via deferred queues) */
    do
-      err = funlock(env->me_fd4data, DXB_BODY);
+      err = funlock(fd4data, DXB_BODY);
    while (err == MDBX_SUCCESS);
    assert(err == ERROR_NOT_LOCKED ||
           (mdbx_RunningUnderWine() && err == ERROR_LOCK_VIOLATION));
    SetLastError(ERROR_SUCCESS);

    do
-      err = funlock(env->me_fd4data, DXB_WHOLE);
+      err = funlock(fd4data, DXB_WHOLE);
    while (err == MDBX_SUCCESS);
    assert(err == ERROR_NOT_LOCKED ||
           (mdbx_RunningUnderWine() && err == ERROR_LOCK_VIOLATION));
@@ -522,7 +539,9 @@ static int internal_seize_lck(HANDLE lfd) {
 }

 MDBX_INTERNAL_FUNC int osal_lck_seize(MDBX_env *env) {
-  assert(env->me_fd4data != INVALID_HANDLE_VALUE);
+  const HANDLE fd4data =
+      env->me_overlapped_fd ? env->me_overlapped_fd : env->me_lazy_fd;
+  assert(fd4data != INVALID_HANDLE_VALUE);
  if (env->me_flags & MDBX_EXCLUSIVE)
    return MDBX_RESULT_TRUE /* nope since files were must be opened
                               non-shareable */
@@ -554,7 +573,7 @@ MDBX_INTERNAL_FUNC int osal_lck_seize(MDBX_env *env) {
      return err;
    }
    jitter4testing(false);
-    err = funlock(env->me_fd4data, DXB_WHOLE);
+    err = funlock(fd4data, DXB_WHOLE);
    if (err != MDBX_SUCCESS)
      mdbx_panic("%s(%s) failed: err %u", __func__,
                 "unlock-against-without-lck", err);
@@ -564,8 +583,10 @@ MDBX_INTERNAL_FUNC int osal_lck_seize(MDBX_env *env) {
 }

 MDBX_INTERNAL_FUNC int osal_lck_downgrade(MDBX_env *env) {
+  const HANDLE fd4data =
+      env->me_overlapped_fd ? env->me_overlapped_fd : env->me_lazy_fd;
  /* Transite from exclusive-write state (E-E) to used (S-?) */
-  assert(env->me_fd4data != INVALID_HANDLE_VALUE);
+  assert(fd4data != INVALID_HANDLE_VALUE);
  assert(env->me_lfd != INVALID_HANDLE_VALUE);

  if (env->me_flags & MDBX_EXCLUSIVE)
@@ -740,7 +761,7 @@ static void WINAPI stub_srwlock_AcquireShared(osal_srwlock_t *srwl) {
    //  If there's a writer already, spin without unnecessarily
    //  interlocking the CPUs
    if (srwl->writerCount != 0) {
-      YieldProcessor();
+      SwitchToThread();
      continue;
    }

@@ -754,7 +775,7 @@ static void WINAPI stub_srwlock_AcquireShared(osal_srwlock_t *srwl) {

    // Remove from the readers list, spin, try again
    _InterlockedDecrement(&srwl->readerCount);
-    YieldProcessor();
+    SwitchToThread();
  }
 }

@@ -770,7 +791,7 @@ static void WINAPI stub_srwlock_AcquireExclusive(osal_srwlock_t *srwl) {
    //  If there's a writer already, spin without unnecessarily
    //  interlocking the CPUs
    if (srwl->writerCount != 0) {
-      YieldProcessor();
+      SwitchToThread();
      continue;
    }

@@ -785,7 +806,7 @@ static void WINAPI stub_srwlock_AcquireExclusive(osal_srwlock_t *srwl) {
  // that we're the writer.
  while (srwl->readerCount != 0) {
    assert(srwl->writerCount >= 0 && srwl->readerCount >= 0);
-    YieldProcessor();
+    SwitchToThread();
  }
 }

@@ -827,38 +848,40 @@ MDBX_SetFileIoOverlappedRange mdbx_SetFileIoOverlappedRange;
 #endif /* GCC/MINGW */

 static void mdbx_winnt_import(void) {
-  const HINSTANCE hNtdll = GetModuleHandleA("ntdll.dll");
-
 #define GET_PROC_ADDR(dll, ENTRY)                                              \
  mdbx_##ENTRY = (MDBX_##ENTRY)GetProcAddress(dll, #ENTRY)

-  if (GetProcAddress(hNtdll, "wine_get_version")) {
-    assert(mdbx_RunningUnderWine());
-  } else {
-    GET_PROC_ADDR(hNtdll, NtFsControlFile);
-    GET_PROC_ADDR(hNtdll, NtExtendSection);
-    assert(!mdbx_RunningUnderWine());
+  const HINSTANCE hNtdll = GetModuleHandleA("ntdll.dll");
+  if (hNtdll) {
+    if (GetProcAddress(hNtdll, "wine_get_version")) {
+      assert(mdbx_RunningUnderWine());
+    } else {
+      GET_PROC_ADDR(hNtdll, NtFsControlFile);
+      GET_PROC_ADDR(hNtdll, NtExtendSection);
+      assert(!mdbx_RunningUnderWine());
+    }
  }

  const HINSTANCE hKernel32dll = GetModuleHandleA("kernel32.dll");
-  GET_PROC_ADDR(hKernel32dll, GetFileInformationByHandleEx);
-  GET_PROC_ADDR(hKernel32dll, GetTickCount64);
-  if (!mdbx_GetTickCount64)
-    mdbx_GetTickCount64 = stub_GetTickCount64;
-  if (!mdbx_RunningUnderWine()) {
-    GET_PROC_ADDR(hKernel32dll, SetFileInformationByHandle);
-    GET_PROC_ADDR(hKernel32dll, GetVolumeInformationByHandleW);
-    GET_PROC_ADDR(hKernel32dll, GetFinalPathNameByHandleW);
-    GET_PROC_ADDR(hKernel32dll, PrefetchVirtualMemory);
-    GET_PROC_ADDR(hKernel32dll, SetFileIoOverlappedRange);
+  if (hKernel32dll) {
+    GET_PROC_ADDR(hKernel32dll, GetFileInformationByHandleEx);
+    GET_PROC_ADDR(hKernel32dll, GetTickCount64);
+    if (!mdbx_GetTickCount64)
+      mdbx_GetTickCount64 = stub_GetTickCount64;
+    if (!mdbx_RunningUnderWine()) {
+      GET_PROC_ADDR(hKernel32dll, SetFileInformationByHandle);
+      GET_PROC_ADDR(hKernel32dll, GetVolumeInformationByHandleW);
+      GET_PROC_ADDR(hKernel32dll, GetFinalPathNameByHandleW);
+      GET_PROC_ADDR(hKernel32dll, PrefetchVirtualMemory);
+      GET_PROC_ADDR(hKernel32dll, SetFileIoOverlappedRange);
+    }
  }

-  const HINSTANCE hAdvapi32dll = GetModuleHandleA("advapi32.dll");
-  GET_PROC_ADDR(hAdvapi32dll, RegGetValueA);
-#undef GET_PROC_ADDR
-
-  const osal_srwlock_t_function init = (osal_srwlock_t_function)GetProcAddress(
-      hKernel32dll, "InitializeSRWLock");
+  const osal_srwlock_t_function init =
+      (osal_srwlock_t_function)(hKernel32dll
+                                    ? GetProcAddress(hKernel32dll,
+                                                     "InitializeSRWLock")
+                                    : nullptr);
  if (init != NULL) {
    osal_srwlock_Init = init;
    osal_srwlock_AcquireShared = (osal_srwlock_t_function)GetProcAddress(
@@ -876,6 +899,12 @@ static void mdbx_winnt_import(void) {
    osal_srwlock_AcquireExclusive = stub_srwlock_AcquireExclusive;
    osal_srwlock_ReleaseExclusive = stub_srwlock_ReleaseExclusive;
  }
+
+  const HINSTANCE hAdvapi32dll = GetModuleHandleA("advapi32.dll");
+  if (hAdvapi32dll) {
+    GET_PROC_ADDR(hAdvapi32dll, RegGetValueA);
+  }
+#undef GET_PROC_ADDR
 }

 #if __GNUC_PREREQ(8, 0)
--- a/src/man1/mdbx_chk.1
+++ b/src/man1/mdbx_chk.1
@@ -1,6 +1,6 @@
-.\" Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>.
+.\" Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>.
 .\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
-.TH MDBX_CHK 1 "2022-11-11" "MDBX 0.12.2"
+.TH MDBX_CHK 1 "2023-03-03" "MDBX 0.12.4"
 .SH NAME
 mdbx_chk \- MDBX checking tool
 .SH SYNOPSIS
--- a/src/man1/mdbx_copy.1
+++ b/src/man1/mdbx_copy.1
@@ -1,8 +1,8 @@
-.\" Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>.
+.\" Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>.
 .\" Copyright 2012-2015 Howard Chu, Symas Corp. All Rights Reserved.
 .\" Copyright 2015,2016 Peter-Service R&D LLC <http://billing.ru/>.
 .\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
-.TH MDBX_COPY 1 "2022-11-11" "MDBX 0.12.2"
+.TH MDBX_COPY 1 "2023-03-03" "MDBX 0.12.4"
 .SH NAME
 mdbx_copy \- MDBX environment copy tool
 .SH SYNOPSIS
--- a/src/man1/mdbx_drop.1
+++ b/src/man1/mdbx_drop.1
@@ -1,7 +1,7 @@
-.\" Copyright 2021-2022 Leonid Yuriev <leo@yuriev.ru>.
+.\" Copyright 2021-2023 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 "2022-11-11" "MDBX 0.12.2"
+.TH MDBX_DROP 1 "2023-03-03" "MDBX 0.12.4"
 .SH NAME
 mdbx_drop \- MDBX database delete tool
 .SH SYNOPSIS
--- a/src/man1/mdbx_dump.1
+++ b/src/man1/mdbx_dump.1
@@ -1,8 +1,8 @@
-.\" Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>.
+.\" Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>.
 .\" Copyright 2014-2015 Howard Chu, Symas Corp. All Rights Reserved.
 .\" Copyright 2015,2016 Peter-Service R&D LLC <http://billing.ru/>.
 .\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
-.TH MDBX_DUMP 1 "2022-11-11" "MDBX 0.12.2"
+.TH MDBX_DUMP 1 "2023-03-03" "MDBX 0.12.4"
 .SH NAME
 mdbx_dump \- MDBX environment export tool
 .SH SYNOPSIS
--- a/src/man1/mdbx_load.1
+++ b/src/man1/mdbx_load.1
@@ -1,8 +1,8 @@
-.\" Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>.
+.\" Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>.
 .\" Copyright 2014-2015 Howard Chu, Symas Corp. All Rights Reserved.
 .\" Copyright 2015,2016 Peter-Service R&D LLC <http://billing.ru/>.
 .\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
-.TH MDBX_LOAD 1 "2022-11-11" "MDBX 0.12.2"
+.TH MDBX_LOAD 1 "2023-03-03" "MDBX 0.12.4"
 .SH NAME
 mdbx_load \- MDBX environment import tool
 .SH SYNOPSIS
--- a/src/man1/mdbx_stat.1
+++ b/src/man1/mdbx_stat.1
@@ -1,8 +1,8 @@
-.\" Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>.
+.\" Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>.
 .\" Copyright 2012-2015 Howard Chu, Symas Corp. All Rights Reserved.
 .\" Copyright 2015,2016 Peter-Service R&D LLC <http://billing.ru/>.
 .\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
-.TH MDBX_STAT 1 "2022-11-11" "MDBX 0.12.2"
+.TH MDBX_STAT 1 "2023-03-03" "MDBX 0.12.4"
 .SH NAME
 mdbx_stat \- MDBX environment status tool
 .SH SYNOPSIS
--- a/src/mdbx.c++
+++ b/src/mdbx.c++
@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2020-2022, Leonid Yuriev <leo@yuriev.ru>.
+// Copyright (c) 2020-2023, Leonid Yuriev <leo@yuriev.ru>.
 // SPDX-License-Identifier: Apache-2.0
 //
 // Non-inline part of the libmdbx C++ API
@@ -14,6 +14,12 @@
 #define __USE_MINGW_ANSI_STDIO 1
 #endif /* MinGW */

+/* Workaround for MSVC' header `extern "C"` vs `std::` redefinition bug */
+#if defined(_MSC_VER) && defined(__SANITIZE_ADDRESS__) &&                      \
+    !defined(_DISABLE_VECTOR_ANNOTATION)
+#define _DISABLE_VECTOR_ANNOTATION
+#endif /* _DISABLE_VECTOR_ANNOTATION */
+
 #include "../mdbx.h++"

 #include "internals.h"
--- a/src/mdbx_chk.c
+++ b/src/mdbx_chk.c
@@ -1,7 +1,7 @@
 /* mdbx_chk.c - memory-mapped database check tool */

 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -23,6 +23,8 @@
 #define xMDBX_TOOLS /* Avoid using internal eASSERT() */
 #include "internals.h"

+#include <ctype.h>
+
 typedef struct flagbit {
  int bit;
  const char *name;
@@ -71,7 +73,7 @@ static void signal_handler(int sig) {
 #define EXIT_FAILURE_CHECK_MINOR EXIT_FAILURE

 typedef struct {
-  const char *name;
+  MDBX_val name;
  struct {
    uint64_t branch, large_count, large_volume, leaf;
    uint64_t subleaf_dupsort, leaf_dupfixed, subleaf_dupfixed;
@@ -102,7 +104,7 @@ uint64_t total_unused_bytes, reclaimable_pages, gc_pages, alloc_pages,
    unused_pages, backed_pages;
 unsigned verbose;
 bool ignore_wrong_order, quiet, dont_traversal;
-const char *only_subdb;
+MDBX_val only_subdb;
 int stuck_meta = -1;

 struct problem {
@@ -125,6 +127,97 @@ static void MDBX_PRINTF_ARGS(1, 2) print(const char *msg, ...) {
  }
 }

+static MDBX_val printable_buf;
+static void free_printable_buf(void) { osal_free(printable_buf.iov_base); }
+
+static const char *sdb_name(const MDBX_val *val) {
+  if (val == MDBX_PGWALK_MAIN)
+    return "@MAIN";
+  if (val == MDBX_PGWALK_GC)
+    return "@GC";
+  if (val == MDBX_PGWALK_META)
+    return "@META";
+
+  const unsigned char *const data = val->iov_base;
+  const size_t len = val->iov_len;
+  if (data == MDBX_PGWALK_MAIN)
+    return "@MAIN";
+  if (data == MDBX_PGWALK_GC)
+    return "@GC";
+  if (data == MDBX_PGWALK_META)
+    return "@META";
+
+  if (!len)
+    return "<zero-length>";
+  if (!data)
+    return "<nullptr>";
+  if (len > 65536) {
+    static char buf[64];
+    /* NOTE: There is MSYS2 MinGW bug if you here got
+     * the "unknown conversion type character ‘z’ in format [-Werror=format=]"
+     * https://stackoverflow.com/questions/74504432/whats-the-proper-way-to-tell-mingw-based-gcc-to-use-ansi-stdio-output-on-windo
+     */
+    snprintf(buf, sizeof(buf), "<too-long-%zu>", len);
+    return buf;
+  }
+
+  bool printable = true;
+  bool quoting = false;
+  size_t xchars = 0;
+  for (size_t i = 0; i < val->iov_len && printable; ++i) {
+    quoting |= data[i] != '_' && isalnum(data[i]) == 0;
+    printable = isprint(data[i]) != 0 ||
+                (data[i] < ' ' && ++xchars < 4 && len > xchars * 4);
+  }
+
+  size_t need = len + 1;
+  if (quoting || !printable)
+    need += len + /* quotes */ 2 + 2 * /* max xchars */ 4;
+  if (need > printable_buf.iov_len) {
+    void *ptr = osal_realloc(printable_buf.iov_base, need);
+    if (!ptr)
+      return "<out-of-memory>";
+    if (!printable_buf.iov_base)
+      atexit(free_printable_buf);
+    printable_buf.iov_base = ptr;
+    printable_buf.iov_len = need;
+  }
+
+  char *out = printable_buf.iov_base;
+  if (!quoting) {
+    memcpy(out, data, len);
+    out += len;
+  } else if (printable) {
+    *out++ = '\'';
+    for (size_t i = 0; i < len; ++i) {
+      if (data[i] < ' ') {
+        assert((char *)printable_buf.iov_base + printable_buf.iov_len >
+               out + 4);
+        static const char hex[] = "0123456789abcdef";
+        out[0] = '\\';
+        out[1] = 'x';
+        out[2] = hex[data[i] >> 4];
+        out[3] = hex[data[i] & 15];
+        out += 4;
+      } else if (strchr("\"'`\\", data[i])) {
+        assert((char *)printable_buf.iov_base + printable_buf.iov_len >
+               out + 2);
+        out[0] = '\\';
+        out[1] = data[i];
+        out += 2;
+      } else {
+        assert((char *)printable_buf.iov_base + printable_buf.iov_len >
+               out + 1);
+        *out++ = data[i];
+      }
+    }
+    *out++ = '\'';
+  }
+  assert((char *)printable_buf.iov_base + printable_buf.iov_len > out);
+  *out = 0;
+  return printable_buf.iov_base;
+}
+
 static void va_log(MDBX_log_level_t level, const char *function, int line,
                   const char *msg, va_list args) {
  static const char *const prefixes[] = {
@@ -190,19 +283,17 @@ static int check_user_break(void) {
 }

 static void pagemap_cleanup(void) {
-  for (size_t i = CORE_DBS + /* account pseudo-entry for meta */ 1;
-       i < ARRAY_LENGTH(walk.dbi); ++i) {
-    if (walk.dbi[i].name) {
-      osal_free((void *)walk.dbi[i].name);
-      walk.dbi[i].name = nullptr;
-    }
-  }
-
  osal_free(walk.pagemap);
  walk.pagemap = nullptr;
 }

-static walk_dbi_t *pagemap_lookup_dbi(const char *dbi_name, bool silent) {
+static bool eq(const MDBX_val a, const MDBX_val b) {
+  return a.iov_len == b.iov_len &&
+         (a.iov_base == b.iov_base || a.iov_len == 0 ||
+          !memcmp(a.iov_base, b.iov_base, a.iov_len));
+}
+
+static walk_dbi_t *pagemap_lookup_dbi(const MDBX_val *dbi_name, bool silent) {
  static walk_dbi_t *last;

  if (dbi_name == MDBX_PGWALK_MAIN)
@@ -212,24 +303,24 @@ static walk_dbi_t *pagemap_lookup_dbi(const char *dbi_name, bool silent) {
  if (dbi_name == MDBX_PGWALK_META)
    return &dbi_meta;

-  if (last && strcmp(last->name, dbi_name) == 0)
+  if (last && eq(last->name, *dbi_name))
    return last;

  walk_dbi_t *dbi = walk.dbi + CORE_DBS + /* account pseudo-entry for meta */ 1;
-  for (; dbi < ARRAY_END(walk.dbi) && dbi->name; ++dbi) {
-    if (strcmp(dbi->name, dbi_name) == 0)
+  for (; dbi < ARRAY_END(walk.dbi) && dbi->name.iov_base; ++dbi) {
+    if (eq(dbi->name, *dbi_name))
      return last = dbi;
  }

  if (verbose > 0 && !silent) {
-    print(" - found '%s' area\n", dbi_name);
+    print(" - found %s area\n", sdb_name(dbi_name));
    fflush(nullptr);
  }

  if (dbi == ARRAY_END(walk.dbi))
    return nullptr;

-  dbi->name = osal_strdup(dbi_name);
+  dbi->name = *dbi_name;
  return last = dbi;
 }

@@ -304,13 +395,13 @@ static size_t problems_pop(struct problem *list) {
 }

 static int pgvisitor(const uint64_t pgno, const unsigned pgnumber,
-                     void *const ctx, const int deep,
-                     const char *const dbi_name_or_tag, const size_t page_size,
-                     const MDBX_page_type_t pagetype, const MDBX_error_t err,
-                     const size_t nentries, const size_t payload_bytes,
-                     const size_t header_bytes, const size_t unused_bytes) {
+                     void *const ctx, const int deep, const MDBX_val *dbi_name,
+                     const size_t page_size, const MDBX_page_type_t pagetype,
+                     const MDBX_error_t err, const size_t nentries,
+                     const size_t payload_bytes, const size_t header_bytes,
+                     const size_t unused_bytes) {
  (void)ctx;
-  const bool is_gc_tree = dbi_name_or_tag == MDBX_PGWALK_GC;
+  const bool is_gc_tree = dbi_name == MDBX_PGWALK_GC;
  if (deep > 42) {
    problem_add("deep", deep, "too large", nullptr);
    data_tree_problems += !is_gc_tree;
@@ -318,7 +409,7 @@ static int pgvisitor(const uint64_t pgno, const unsigned pgnumber,
    return MDBX_CORRUPTED /* avoid infinite loop/recursion */;
  }

-  walk_dbi_t *dbi = pagemap_lookup_dbi(dbi_name_or_tag, false);
+  walk_dbi_t *dbi = pagemap_lookup_dbi(dbi_name, false);
  if (!dbi) {
    data_tree_problems += !is_gc_tree;
    gc_tree_problems += is_gc_tree;
@@ -383,14 +474,14 @@ static int pgvisitor(const uint64_t pgno, const unsigned pgnumber,
  }

  if (pgnumber) {
-    if (verbose > 3 && (!only_subdb || strcmp(only_subdb, dbi->name) == 0)) {
+    if (verbose > 3 && (!only_subdb.iov_base || eq(only_subdb, dbi->name))) {
      if (pgnumber == 1)
        print("     %s-page %" PRIu64, pagetype_caption, pgno);
      else
        print("     %s-span %" PRIu64 "[%u]", pagetype_caption, pgno, pgnumber);
      print(" of %s: header %" PRIiPTR ", %s %" PRIiPTR ", payload %" PRIiPTR
            ", unused %" PRIiPTR ", deep %i\n",
-            dbi->name, header_bytes,
+            sdb_name(&dbi->name), header_bytes,
            (pagetype == MDBX_page_branch) ? "keys" : "entries", nentries,
            payload_bytes, unused_bytes, deep);
    }
@@ -408,8 +499,8 @@ static int pgvisitor(const uint64_t pgno, const unsigned pgnumber,
        walk_dbi_t *coll_dbi = &walk.dbi[walk.pagemap[spanpgno] - 1];
        problem_add("page", spanpgno,
                    (branch && coll_dbi == dbi) ? "loop" : "already used",
-                    "%s-page: by %s, deep %i", pagetype_caption, coll_dbi->name,
-                    deep);
+                    "%s-page: by %s, deep %i", pagetype_caption,
+                    sdb_name(&coll_dbi->name), deep);
        already_used = true;
        data_tree_problems += !is_gc_tree;
        gc_tree_problems += is_gc_tree;
@@ -480,8 +571,8 @@ static int pgvisitor(const uint64_t pgno, const unsigned pgnumber,
        data_tree_problems += !is_gc_tree;
        gc_tree_problems += is_gc_tree;
      } else {
-        dbi->payload_bytes += payload_bytes + header_bytes;
-        walk.total_payload_bytes += payload_bytes + header_bytes;
+        dbi->payload_bytes += (uint64_t)payload_bytes + header_bytes;
+        walk.total_payload_bytes += (uint64_t)payload_bytes + header_bytes;
      }
    }
  }
@@ -491,8 +582,8 @@ static int pgvisitor(const uint64_t pgno, const unsigned pgnumber,

 typedef int(visitor)(const uint64_t record_number, const MDBX_val *key,
                     const MDBX_val *data);
-static int process_db(MDBX_dbi dbi_handle, char *dbi_name, visitor *handler,
-                      bool silent);
+static int process_db(MDBX_dbi dbi_handle, const MDBX_val *dbi_name,
+                      visitor *handler);

 static int handle_userdb(const uint64_t record_number, const MDBX_val *key,
                         const MDBX_val *data) {
@@ -541,7 +632,7 @@ static int handle_freedb(const uint64_t record_number, const MDBX_val *key,

      pgno_t prev = MDBX_PNL_ASCENDING ? NUM_METAS - 1 : txn->mt_next_pgno;
      pgno_t span = 1;
-      for (unsigned i = 0; i < number; ++i) {
+      for (size_t i = 0; i < number; ++i) {
        if (check_user_break())
          return MDBX_EINTR;
        const pgno_t pgno = iptr[i];
@@ -560,7 +651,7 @@ static int handle_freedb(const uint64_t record_number, const MDBX_val *key,
          if (MDBX_PNL_DISORDERED(prev, pgno)) {
            bad = " [bad sequence]";
            problem_add("entry", txnid, "bad sequence",
-                        "%" PRIaPGNO " %c [%u].%" PRIaPGNO, prev,
+                        "%" PRIaPGNO " %c [%zu].%" PRIaPGNO, prev,
                        (prev == pgno) ? '=' : (MDBX_PNL_ASCENDING ? '>' : '<'),
                        i, pgno);
          }
@@ -570,7 +661,7 @@ static int handle_freedb(const uint64_t record_number, const MDBX_val *key,
              walk.pagemap[pgno] = -1;
            else if (idx > 0)
              problem_add("page", pgno, "already used", "by %s",
-                          walk.dbi[idx - 1].name);
+                          sdb_name(&walk.dbi[idx - 1].name));
            else
              problem_add("page", pgno, "already listed in GC", nullptr);
          }
@@ -581,12 +672,12 @@ static int handle_freedb(const uint64_t record_number, const MDBX_val *key,
                                                     : pgno_sub(pgno, span)))
          ++span;
      }
-      if (verbose > 3 && !only_subdb) {
+      if (verbose > 3 && !only_subdb.iov_base) {
        print("     transaction %" PRIaTXN ", %" PRIuPTR
              " pages, maxspan %" PRIaPGNO "%s\n",
              txnid, number, span, bad);
        if (verbose > 4) {
-          for (unsigned i = 0; i < number; i += span) {
+          for (size_t i = 0; i < number; i += span) {
            const pgno_t pgno = iptr[i];
            for (span = 1;
                 i + span < number &&
@@ -608,36 +699,18 @@ static int handle_freedb(const uint64_t record_number, const MDBX_val *key,
 }

 static int equal_or_greater(const MDBX_val *a, const MDBX_val *b) {
-  return (a->iov_len == b->iov_len &&
-          memcmp(a->iov_base, b->iov_base, a->iov_len) == 0)
-             ? 0
-             : 1;
+  return eq(*a, *b) ? 0 : 1;
 }

 static int handle_maindb(const uint64_t record_number, const MDBX_val *key,
                         const MDBX_val *data) {
-  char *name;
-  int rc;
-  size_t i;
-
-  name = key->iov_base;
-  for (i = 0; i < key->iov_len; ++i) {
-    if (name[i] < ' ')
-      return handle_userdb(record_number, key, data);
+  if (data->iov_len == sizeof(MDBX_db)) {
+    int rc = process_db(~0u, key, handle_userdb);
+    if (rc != MDBX_INCOMPATIBLE) {
+      userdb_count++;
+      return rc;
+    }
  }
-
-  name = osal_malloc(key->iov_len + 1);
-  if (unlikely(!name))
-    return MDBX_ENOMEM;
-  memcpy(name, key->iov_base, key->iov_len);
-  name[key->iov_len] = '\0';
-  userdb_count++;
-
-  rc = process_db(~0u, name, handle_userdb, false);
-  osal_free(name);
-  if (rc != MDBX_INCOMPATIBLE)
-    return rc;
-
  return handle_userdb(record_number, key, data);
 }

@@ -691,8 +764,8 @@ static const char *db_flags2valuemode(unsigned flags) {
  }
 }

-static int process_db(MDBX_dbi dbi_handle, char *dbi_name, visitor *handler,
-                      bool silent) {
+static int process_db(MDBX_dbi dbi_handle, const MDBX_val *dbi_name,
+                      visitor *handler) {
  MDBX_cursor *mc;
  MDBX_stat ms;
  MDBX_val key, data;
@@ -701,18 +774,19 @@ static int process_db(MDBX_dbi dbi_handle, char *dbi_name, visitor *handler,
  int rc, i;
  struct problem *saved_list;
  uint64_t problems_count;
+  const bool second_pass = dbi_handle == MAIN_DBI;

  uint64_t record_count = 0, dups = 0;
  uint64_t key_bytes = 0, data_bytes = 0;

  if ((MDBX_TXN_FINISHED | MDBX_TXN_ERROR) & mdbx_txn_flags(txn)) {
-    print(" ! abort processing '%s' due to a previous error\n",
-          dbi_name ? dbi_name : "@MAIN");
+    print(" ! abort processing %s due to a previous error\n",
+          sdb_name(dbi_name));
    return MDBX_BAD_TXN;
  }

  if (dbi_handle == ~0u) {
-    rc = mdbx_dbi_open_ex(
+    rc = mdbx_dbi_open_ex2(
        txn, dbi_name, MDBX_DB_ACCEDE, &dbi_handle,
        (dbi_name && ignore_wrong_order) ? equal_or_greater : nullptr,
        (dbi_name && ignore_wrong_order) ? equal_or_greater : nullptr);
@@ -720,27 +794,26 @@ static int process_db(MDBX_dbi dbi_handle, char *dbi_name, visitor *handler,
      if (!dbi_name ||
          rc !=
              MDBX_INCOMPATIBLE) /* LY: mainDB's record is not a user's DB. */ {
-        error("mdbx_dbi_open('%s') failed, error %d %s\n",
-              dbi_name ? dbi_name : "main", rc, mdbx_strerror(rc));
+        error("mdbx_dbi_open(%s) failed, error %d %s\n", sdb_name(dbi_name), rc,
+              mdbx_strerror(rc));
      }
      return rc;
    }
  }

-  if (dbi_handle >= CORE_DBS && dbi_name && only_subdb &&
-      strcmp(only_subdb, dbi_name) != 0) {
+  if (dbi_handle >= CORE_DBS && dbi_name && only_subdb.iov_base &&
+      !eq(only_subdb, *dbi_name)) {
    if (verbose) {
-      print("Skip processing '%s'...\n", dbi_name);
+      print("Skip processing %s...\n", sdb_name(dbi_name));
      fflush(nullptr);
    }
    skipped_subdb++;
    return MDBX_SUCCESS;
  }

-  if (!silent && verbose) {
-    print("Processing '%s'...\n", dbi_name ? dbi_name : "@MAIN");
-    fflush(nullptr);
-  }
+  if (!second_pass && verbose)
+    print("Processing %s...\n", sdb_name(dbi_name));
+  fflush(nullptr);

  rc = mdbx_dbi_flags(txn, dbi_handle, &flags);
  if (rc) {
@@ -754,7 +827,7 @@ static int process_db(MDBX_dbi dbi_handle, char *dbi_name, visitor *handler,
    return rc;
  }

-  if (!silent && verbose) {
+  if (!second_pass && verbose) {
    print(" - key-value kind: %s-key => %s-value", db_flags2keymode(flags),
          db_flags2valuemode(flags));
    if (verbose > 1) {
@@ -830,57 +903,75 @@ static int process_db(MDBX_dbi dbi_handle, char *dbi_name, visitor *handler,
    if (rc)
      goto bailout;

-    bool bad_key = false;
-    if (key.iov_len > maxkeysize) {
-      problem_add("entry", record_count, "key length exceeds max-key-size",
-                  "%" PRIuPTR " > %" PRIuPTR, key.iov_len, maxkeysize);
-      bad_key = true;
-    } else if ((flags & MDBX_INTEGERKEY) && key.iov_len != sizeof(uint64_t) &&
-               key.iov_len != sizeof(uint32_t)) {
-      problem_add("entry", record_count, "wrong key length",
-                  "%" PRIuPTR " != 4or8", key.iov_len);
-      bad_key = true;
-    }
+    if (!second_pass) {
+      bool bad_key = false;
+      if (key.iov_len > maxkeysize) {
+        problem_add("entry", record_count, "key length exceeds max-key-size",
+                    "%" PRIuPTR " > %" PRIuPTR, key.iov_len, maxkeysize);
+        bad_key = true;
+      } else if ((flags & MDBX_INTEGERKEY) && key.iov_len != sizeof(uint64_t) &&
+                 key.iov_len != sizeof(uint32_t)) {
+        problem_add("entry", record_count, "wrong key length",
+                    "%" PRIuPTR " != 4or8", key.iov_len);
+        bad_key = true;
+      }

-    bool bad_data = false;
-    if ((flags & MDBX_INTEGERDUP) && data.iov_len != sizeof(uint64_t) &&
-        data.iov_len != sizeof(uint32_t)) {
-      problem_add("entry", record_count, "wrong data length",
-                  "%" PRIuPTR " != 4or8", data.iov_len);
-      bad_data = true;
-    }
-
-    if (prev_key.iov_base) {
-      if (prev_data.iov_base && !bad_data && (flags & MDBX_DUPFIXED) &&
-          prev_data.iov_len != data.iov_len) {
-        problem_add("entry", record_count, "different data length",
-                    "%" PRIuPTR " != %" PRIuPTR, prev_data.iov_len,
-                    data.iov_len);
+      bool bad_data = false;
+      if ((flags & MDBX_INTEGERDUP) && data.iov_len != sizeof(uint64_t) &&
+          data.iov_len != sizeof(uint32_t)) {
+        problem_add("entry", record_count, "wrong data length",
+                    "%" PRIuPTR " != 4or8", data.iov_len);
        bad_data = true;
      }

-      if (!bad_key) {
-        int cmp = mdbx_cmp(txn, dbi_handle, &key, &prev_key);
-        if (cmp == 0) {
-          ++dups;
-          if ((flags & MDBX_DUPSORT) == 0) {
-            problem_add("entry", record_count, "duplicated entries", nullptr);
-            if (prev_data.iov_base && data.iov_len == prev_data.iov_len &&
-                memcmp(data.iov_base, prev_data.iov_base, data.iov_len) == 0) {
-              problem_add("entry", record_count, "complete duplicate", nullptr);
-            }
-          } else if (!bad_data && prev_data.iov_base) {
-            cmp = mdbx_dcmp(txn, dbi_handle, &data, &prev_data);
-            if (cmp == 0) {
-              problem_add("entry", record_count, "complete duplicate", nullptr);
-            } else if (cmp < 0 && !ignore_wrong_order) {
-              problem_add("entry", record_count, "wrong order of multi-values",
-                          nullptr);
-            }
-          }
-        } else if (cmp < 0 && !ignore_wrong_order) {
-          problem_add("entry", record_count, "wrong order of entries", nullptr);
+      if (prev_key.iov_base) {
+        if (prev_data.iov_base && !bad_data && (flags & MDBX_DUPFIXED) &&
+            prev_data.iov_len != data.iov_len) {
+          problem_add("entry", record_count, "different data length",
+                      "%" PRIuPTR " != %" PRIuPTR, prev_data.iov_len,
+                      data.iov_len);
+          bad_data = true;
        }
+
+        if (!bad_key) {
+          int cmp = mdbx_cmp(txn, dbi_handle, &key, &prev_key);
+          if (cmp == 0) {
+            ++dups;
+            if ((flags & MDBX_DUPSORT) == 0) {
+              problem_add("entry", record_count, "duplicated entries", nullptr);
+              if (prev_data.iov_base && data.iov_len == prev_data.iov_len &&
+                  memcmp(data.iov_base, prev_data.iov_base, data.iov_len) ==
+                      0) {
+                problem_add("entry", record_count, "complete duplicate",
+                            nullptr);
+              }
+            } else if (!bad_data && prev_data.iov_base) {
+              cmp = mdbx_dcmp(txn, dbi_handle, &data, &prev_data);
+              if (cmp == 0) {
+                problem_add("entry", record_count, "complete duplicate",
+                            nullptr);
+              } else if (cmp < 0 && !ignore_wrong_order) {
+                problem_add("entry", record_count,
+                            "wrong order of multi-values", nullptr);
+              }
+            }
+          } else if (cmp < 0 && !ignore_wrong_order) {
+            problem_add("entry", record_count, "wrong order of entries",
+                        nullptr);
+          }
+        }
+      }
+
+      if (!bad_key) {
+        if (verbose && (flags & MDBX_INTEGERKEY) && !prev_key.iov_base)
+          print(" - fixed key-size %" PRIuPTR "\n", key.iov_len);
+        prev_key = key;
+      }
+      if (!bad_data) {
+        if (verbose && (flags & (MDBX_INTEGERDUP | MDBX_DUPFIXED)) &&
+            !prev_data.iov_base)
+          print(" - fixed data-size %" PRIuPTR "\n", data.iov_len);
+        prev_data = data;
      }
    }

@@ -894,17 +985,6 @@ static int process_db(MDBX_dbi dbi_handle, char *dbi_name, visitor *handler,
    key_bytes += key.iov_len;
    data_bytes += data.iov_len;

-    if (!bad_key) {
-      if (verbose && (flags & MDBX_INTEGERKEY) && !prev_key.iov_base)
-        print(" - fixed key-size %" PRIuPTR "\n", key.iov_len);
-      prev_key = key;
-    }
-    if (!bad_data) {
-      if (verbose && (flags & (MDBX_INTEGERDUP | MDBX_DUPFIXED)) &&
-          !prev_data.iov_base)
-        print(" - fixed data-size %" PRIuPTR "\n", data.iov_len);
-      prev_data = data;
-    }
    rc = mdbx_cursor_get(mc, &key, &data, MDBX_NEXT);
  }
  if (rc != MDBX_NOTFOUND)
@@ -917,7 +997,7 @@ static int process_db(MDBX_dbi dbi_handle, char *dbi_name, visitor *handler,
                "%" PRIu64 " != %" PRIu64, record_count, ms.ms_entries);
 bailout:
  problems_count = problems_pop(saved_list);
-  if (!silent && verbose) {
+  if (!second_pass && verbose) {
    print(" - summary: %" PRIu64 " records, %" PRIu64 " dups, %" PRIu64
          " key's bytes, %" PRIu64 " data's "
          "bytes, %" PRIu64 " problems\n",
@@ -1102,9 +1182,9 @@ int main(int argc, char *argv[]) {
  }
 #endif

-  dbi_meta.name = "@META";
-  dbi_free.name = "@GC";
-  dbi_main.name = "@MAIN";
+  dbi_meta.name.iov_base = MDBX_PGWALK_META;
+  dbi_free.name.iov_base = MDBX_PGWALK_GC;
+  dbi_main.name.iov_base = MDBX_PGWALK_MAIN;
  atexit(pagemap_cleanup);

  if (argc < 2)
@@ -1171,7 +1251,7 @@ int main(int argc, char *argv[]) {
      envflags &= ~MDBX_RDONLY;
 #if MDBX_MMAP_INCOHERENT_FILE_WRITE
      /* Temporary `workaround` for OpenBSD kernel's flaw.
-       * See https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/67 */
+       * See https://libmdbx.dqdkfa.ru/dead-github/issues/67 */
      envflags |= MDBX_WRITEMAP;
 #endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
      break;
@@ -1182,9 +1262,10 @@ int main(int argc, char *argv[]) {
      dont_traversal = true;
      break;
    case 's':
-      if (only_subdb && strcmp(only_subdb, optarg))
+      if (only_subdb.iov_base && strcmp(only_subdb.iov_base, optarg))
        usage(prog);
-      only_subdb = optarg;
+      only_subdb.iov_base = optarg;
+      only_subdb.iov_len = strlen(optarg);
      break;
    case 'i':
      ignore_wrong_order = true;
@@ -1222,9 +1303,10 @@ int main(int argc, char *argv[]) {
      error("write-mode must be enabled to turn to the specified meta-page.\n");
      rc = EXIT_INTERRUPTED;
    }
-    if (only_subdb || dont_traversal) {
-      error("whole database checking with tree-traversal are required to turn "
-            "to the specified meta-page.\n");
+    if (only_subdb.iov_base || dont_traversal) {
+      error(
+          "whole database checking with b-tree traversal are required to turn "
+          "to the specified meta-page.\n");
      rc = EXIT_INTERRUPTED;
    }
  }
@@ -1415,7 +1497,7 @@ int main(int argc, char *argv[]) {
      alloc_pages = backed_pages;
    }
  } else {
-    /* LY: DB may be shrinked by writer down to the allocated pages. */
+    /* LY: DB may be shrunk by writer down to the allocated pages. */
    if (alloc_pages > backed_pages) {
      print(" ! alloc-pages %" PRIu64 " > backed-pages %" PRIu64 "\n",
            alloc_pages, backed_pages);
@@ -1563,8 +1645,8 @@ int main(int argc, char *argv[]) {
        unused_pages += 1;

    empty_pages = lost_bytes = 0;
-    for (walk_dbi_t *dbi = &dbi_main; dbi < ARRAY_END(walk.dbi) && dbi->name;
-         ++dbi) {
+    for (walk_dbi_t *dbi = &dbi_main;
+         dbi < ARRAY_END(walk.dbi) && dbi->name.iov_base; ++dbi) {
      empty_pages += dbi->pages.empty;
      lost_bytes += dbi->lost_bytes;
    }
@@ -1574,9 +1656,10 @@ int main(int argc, char *argv[]) {
      print(" - pages: walked %" PRIu64 ", left/unused %" PRIu64 "\n",
            walk.pgcount, unused_pages);
      if (verbose > 1) {
-        for (walk_dbi_t *dbi = walk.dbi; dbi < ARRAY_END(walk.dbi) && dbi->name;
-             ++dbi) {
-          print("     %s: subtotal %" PRIu64, dbi->name, dbi->pages.total);
+        for (walk_dbi_t *dbi = walk.dbi;
+             dbi < ARRAY_END(walk.dbi) && dbi->name.iov_base; ++dbi) {
+          print("     %s: subtotal %" PRIu64, sdb_name(&dbi->name),
+                dbi->pages.total);
          if (dbi->pages.other && dbi->pages.other != dbi->pages.total)
            print(", other %" PRIu64, dbi->pages.other);
          if (dbi->pages.branch)
@@ -1608,14 +1691,15 @@ int main(int argc, char *argv[]) {
              (total_page_bytes - walk.total_payload_bytes) * 100.0 /
                  total_page_bytes);
      if (verbose > 2) {
-        for (walk_dbi_t *dbi = walk.dbi; dbi < ARRAY_END(walk.dbi) && dbi->name;
-             ++dbi)
+        for (walk_dbi_t *dbi = walk.dbi;
+             dbi < ARRAY_END(walk.dbi) && dbi->name.iov_base; ++dbi)
          if (dbi->pages.total) {
            uint64_t dbi_bytes = dbi->pages.total * envinfo.mi_dxb_pagesize;
            print("     %s: subtotal %" PRIu64 " bytes (%.1f%%),"
                  " payload %" PRIu64 " (%.1f%%), unused %" PRIu64 " (%.1f%%)",
-                  dbi->name, dbi_bytes, dbi_bytes * 100.0 / total_page_bytes,
-                  dbi->payload_bytes, dbi->payload_bytes * 100.0 / dbi_bytes,
+                  sdb_name(&dbi->name), dbi_bytes,
+                  dbi_bytes * 100.0 / total_page_bytes, dbi->payload_bytes,
+                  dbi->payload_bytes * 100.0 / dbi_bytes,
                  dbi_bytes - dbi->payload_bytes,
                  (dbi_bytes - dbi->payload_bytes) * 100.0 / dbi_bytes);
            if (dbi->pages.empty)
@@ -1624,7 +1708,7 @@ int main(int argc, char *argv[]) {
              print(", %" PRIu64 " bytes lost", dbi->lost_bytes);
            print("\n");
          } else
-            print("     %s: empty\n", dbi->name);
+            print("     %s: empty\n", sdb_name(&dbi->name));
      }
      print(" - summary: average fill %.1f%%",
            walk.total_payload_bytes * 100.0 / total_page_bytes);
@@ -1639,21 +1723,12 @@ int main(int argc, char *argv[]) {
    fflush(nullptr);
  }

-  if (!verbose)
-    print("Iterating DBIs...\n");
-  if (data_tree_problems) {
-    print("Skip processing %s since tree is corrupted (%u problems)\n", "@MAIN",
-          data_tree_problems);
-    problems_maindb = data_tree_problems;
-  } else
-    problems_maindb = process_db(~0u, /* MAIN_DBI */ nullptr, nullptr, false);
-
  if (gc_tree_problems) {
-    print("Skip processing %s since tree is corrupted (%u problems)\n", "@GC",
-          gc_tree_problems);
+    print("Skip processing %s since %s is corrupted (%u problems)\n", "@GC",
+          "b-tree", gc_tree_problems);
    problems_freedb = gc_tree_problems;
  } else
-    problems_freedb = process_db(FREE_DBI, "@GC", handle_freedb, false);
+    problems_freedb = process_db(FREE_DBI, MDBX_PGWALK_GC, handle_freedb);

  if (verbose) {
    uint64_t value = envinfo.mi_mapsize / envinfo.mi_dxb_pagesize;
@@ -1685,7 +1760,7 @@ int main(int argc, char *argv[]) {
    print(", available %" PRIu64 " (%.1f%%)\n", value, value / percent);
  }

-  if (problems_maindb == 0 && problems_freedb == 0) {
+  if ((problems_maindb = data_tree_problems) == 0 && problems_freedb == 0) {
    if (!dont_traversal &&
        (envflags & (MDBX_EXCLUSIVE | MDBX_RDONLY)) != MDBX_RDONLY) {
      if (walk.pgcount != alloc_pages - gc_pages) {
@@ -1694,22 +1769,32 @@ int main(int argc, char *argv[]) {
              walk.pgcount, alloc_pages - gc_pages);
      }
      if (unused_pages != gc_pages) {
-        error("gc pages mismatch (%" PRIu64 "(expected) != %" PRIu64 "(GC))\n",
+        error("GC pages mismatch (%" PRIu64 "(expected) != %" PRIu64 "(GC))\n",
              unused_pages, gc_pages);
      }
    } else if (verbose) {
-      print(" - skip check used and gc pages (btree-traversal with "
+      print(" - skip check used and GC pages (btree-traversal with "
            "monopolistic or read-write mode only)\n");
    }

-    if (!process_db(MAIN_DBI, nullptr, handle_maindb, true)) {
-      if (!userdb_count && verbose)
-        print(" - does not contain multiple databases\n");
+    problems_maindb = process_db(~0u, /* MAIN_DBI */ nullptr, nullptr);
+    if (problems_maindb == 0) {
+      print("Scanning %s for %s...\n", "@MAIN", "sub-database(s)");
+      if (!process_db(MAIN_DBI, nullptr, handle_maindb)) {
+        if (!userdb_count && verbose)
+          print(" - does not contain multiple databases\n");
+      }
+    } else {
+      print("Skip processing %s since %s is corrupted (%u problems)\n",
+            "sub-database(s)", "@MAIN", problems_maindb);
    }
+  } else {
+    print("Skip processing %s since %s is corrupted (%u problems)\n", "@MAIN",
+          "b-tree", data_tree_problems);
  }

  if (rc == 0 && total_problems == 1 && problems_meta == 1 && !dont_traversal &&
-      (envflags & MDBX_RDONLY) == 0 && !only_subdb && stuck_meta < 0 &&
+      (envflags & MDBX_RDONLY) == 0 && !only_subdb.iov_base && stuck_meta < 0 &&
      get_meta_txnid(meta_recent(true)) < envinfo.mi_recent_txnid) {
    print("Perform sync-to-disk for make steady checkpoint at txn-id #%" PRIi64
          "\n",
@@ -1728,7 +1813,7 @@ int main(int argc, char *argv[]) {
    }
  }

-  if (turn_meta && stuck_meta >= 0 && !dont_traversal && !only_subdb &&
+  if (turn_meta && stuck_meta >= 0 && !dont_traversal && !only_subdb.iov_base &&
      (envflags & (MDBX_RDONLY | MDBX_EXCLUSIVE)) == MDBX_EXCLUSIVE) {
    const bool successful_check = (rc | total_problems | problems_meta) == 0;
    if (successful_check || force_turn_meta) {
--- a/src/mdbx_copy.c
+++ b/src/mdbx_copy.c
@@ -1,7 +1,7 @@
 /* mdbx_copy.c - memory-mapped database backup tool */

 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/src/mdbx_drop.c
+++ b/src/mdbx_drop.c
@@ -1,10 +1,10 @@
 /* mdbx_drop.c - memory-mapped database delete tool */

 /*
- * Copyright 2021 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2021-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 *
- * Copyright 2016-2022 Howard Chu, Symas Corp.
+ * Copyright 2016-2021 Howard Chu, Symas Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
--- a/src/mdbx_dump.c
+++ b/src/mdbx_dump.c
@@ -1,7 +1,7 @@
 /* mdbx_dump.c - memory-mapped database dump tool */

 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -66,7 +66,7 @@ static const char hexc[] = "0123456789abcdef";

 static void dumpbyte(unsigned char c) {
  putchar(hexc[c >> 4]);
-  putchar(hexc[c & 0xf]);
+  putchar(hexc[c & 15]);
 }

 static void text(MDBX_val *v) {
--- a/src/mdbx_load.c
+++ b/src/mdbx_load.c
@@ -1,7 +1,7 @@
 /* mdbx_load.c - memory-mapped database load tool */

 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -673,7 +673,7 @@ int main(int argc, char *argv[]) {
    goto env_close;
  }

-  kbuf.iov_len = mdbx_env_get_maxvalsize_ex(env, 0) + 1;
+  kbuf.iov_len = mdbx_env_get_maxvalsize_ex(env, 0) + (size_t)1;
  if (kbuf.iov_len >= INTPTR_MAX / 2) {
    if (!quiet)
      fprintf(stderr, "mdbx_env_get_maxkeysize() failed, returns %zu\n",
--- a/src/mdbx_stat.c
+++ b/src/mdbx_stat.c
@@ -1,7 +1,7 @@
 /* mdbx_stat.c - memory-mapped database status tool */

 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -256,6 +256,17 @@ int main(int argc, char *argv[]) {
    printf("      WOP: %8" PRIu64
           "\t// number of explicit write operations (not a pages) to a disk\n",
           mei.mi_pgop_stat.wops);
+    printf(" PreFault: %8" PRIu64
+           "\t// number of prefault write operations (not a pages)\n",
+           mei.mi_pgop_stat.prefault);
+    printf("  mInCore: %8" PRIu64 "\t// number of mincore() calls\n",
+           mei.mi_pgop_stat.mincore);
+    printf("    mSync: %8" PRIu64
+           "\t// number of explicit msync-to-disk operations (not a pages)\n",
+           mei.mi_pgop_stat.msync);
+    printf("    fSync: %8" PRIu64
+           "\t// number of explicit fsync-to-disk operations (not a pages)\n",
+           mei.mi_pgop_stat.fsync);
  }

  if (envinfo) {
--- a/src/options.h
+++ b/src/options.h
@@ -40,6 +40,8 @@
 #define MDBX_ENV_CHECKPID 1
 #endif
 #define MDBX_ENV_CHECKPID_CONFIG "AUTO=" MDBX_STRINGIFY(MDBX_ENV_CHECKPID)
+#elif !(MDBX_ENV_CHECKPID == 0 || MDBX_ENV_CHECKPID == 1)
+#error MDBX_ENV_CHECKPID must be defined as 0 or 1
 #else
 #define MDBX_ENV_CHECKPID_CONFIG MDBX_STRINGIFY(MDBX_ENV_CHECKPID)
 #endif /* MDBX_ENV_CHECKPID */
@@ -49,6 +51,8 @@
 #ifndef MDBX_TXN_CHECKOWNER
 #define MDBX_TXN_CHECKOWNER 1
 #define MDBX_TXN_CHECKOWNER_CONFIG "AUTO=" MDBX_STRINGIFY(MDBX_TXN_CHECKOWNER)
+#elif !(MDBX_TXN_CHECKOWNER == 0 || MDBX_TXN_CHECKOWNER == 1)
+#error MDBX_TXN_CHECKOWNER must be defined as 0 or 1
 #else
 #define MDBX_TXN_CHECKOWNER_CONFIG MDBX_STRINGIFY(MDBX_TXN_CHECKOWNER)
 #endif /* MDBX_TXN_CHECKOWNER */
@@ -62,6 +66,8 @@
 #define MDBX_TRUST_RTC 1
 #endif
 #define MDBX_TRUST_RTC_CONFIG "AUTO=" MDBX_STRINGIFY(MDBX_TRUST_RTC)
+#elif !(MDBX_TRUST_RTC == 0 || MDBX_TRUST_RTC == 1)
+#error MDBX_TRUST_RTC must be defined as 0 or 1
 #else
 #define MDBX_TRUST_RTC_CONFIG MDBX_STRINGIFY(MDBX_TRUST_RTC)
 #endif /* MDBX_TRUST_RTC */
@@ -87,6 +93,19 @@
 #error MDBX_ENABLE_PGOP_STAT must be defined as 0 or 1
 #endif /* MDBX_ENABLE_PGOP_STAT */

+/** Controls using Unix' mincore() to determine whether DB-pages
+ * are resident in memory. */
+#ifndef MDBX_ENABLE_MINCORE
+#if MDBX_ENABLE_PREFAULT &&                                                    \
+    (defined(MINCORE_INCORE) || !(defined(_WIN32) || defined(_WIN64)))
+#define MDBX_ENABLE_MINCORE 1
+#else
+#define MDBX_ENABLE_MINCORE 0
+#endif
+#elif !(MDBX_ENABLE_MINCORE == 0 || MDBX_ENABLE_MINCORE == 1)
+#error MDBX_ENABLE_MINCORE must be defined as 0 or 1
+#endif /* MDBX_ENABLE_MINCORE */
+
 /** Enables chunking long list of retired pages during huge transactions commit
 * to avoid use sequences of pages. */
 #ifndef MDBX_ENABLE_BIGFOOT
@@ -147,7 +166,7 @@

 /** 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 builded with
+ * \warning The database format depend on this option and libmdbx built with
 * different option value are incompatible. */
 #ifndef MDBX_PNL_ASCENDING
 #define MDBX_PNL_ASCENDING 0
@@ -201,7 +220,11 @@
 #endif /* MDBX_HAVE_C11ATOMICS */

 /** If defined then enables use the GCC's `__builtin_cpu_supports()`
- *  for runtime dispatching depending on the CPU's capabilities. */
+ * for runtime dispatching depending on the CPU's capabilities.
+ * \note Defining `MDBX_HAVE_BUILTIN_CPU_SUPPORTS` to `0` should avoided unless
+ * build for particular single-target platform, since on AMD64/x86 this disables
+ * dynamic choice (at runtime) of SSE2 / AVX2 / AVX512 instructions
+ * with fallback to non-accelerated baseline code. */
 #ifndef MDBX_HAVE_BUILTIN_CPU_SUPPORTS
 #if defined(__APPLE__) || defined(BIONIC)
 /* Never use any modern features on Apple's or Google's OSes
@@ -287,6 +310,8 @@
 #define MDBX_USE_OFDLOCKS 0
 #endif
 #define MDBX_USE_OFDLOCKS_CONFIG "AUTO=" MDBX_STRINGIFY(MDBX_USE_OFDLOCKS)
+#elif !(MDBX_USE_OFDLOCKS == 0 || MDBX_USE_OFDLOCKS == 1)
+#error MDBX_USE_OFDLOCKS must be defined as 0 or 1
 #else
 #define MDBX_USE_OFDLOCKS_CONFIG MDBX_STRINGIFY(MDBX_USE_OFDLOCKS)
 #endif /* MDBX_USE_OFDLOCKS */
@@ -300,6 +325,8 @@
 #else
 #define MDBX_USE_SENDFILE 0
 #endif
+#elif !(MDBX_USE_SENDFILE == 0 || MDBX_USE_SENDFILE == 1)
+#error MDBX_USE_SENDFILE must be defined as 0 or 1
 #endif /* MDBX_USE_SENDFILE */

 /** Advanced: Using copy_file_range() syscall (autodetection by default). */
@@ -309,6 +336,8 @@
 #else
 #define MDBX_USE_COPYFILERANGE 0
 #endif
+#elif !(MDBX_USE_COPYFILERANGE == 0 || MDBX_USE_COPYFILERANGE == 1)
+#error MDBX_USE_COPYFILERANGE must be defined as 0 or 1
 #endif /* MDBX_USE_COPYFILERANGE */

 /** Advanced: Using sync_file_range() syscall (autodetection by default). */
@@ -320,6 +349,8 @@
 #else
 #define MDBX_USE_SYNCFILERANGE 0
 #endif
+#elif !(MDBX_USE_SYNCFILERANGE == 0 || MDBX_USE_SYNCFILERANGE == 1)
+#error MDBX_USE_SYNCFILERANGE must be defined as 0 or 1
 #endif /* MDBX_USE_SYNCFILERANGE */

 //------------------------------------------------------------------------------
@@ -331,6 +362,9 @@
 #else
 #define MDBX_CPU_WRITEBACK_INCOHERENT 1
 #endif
+#elif !(MDBX_CPU_WRITEBACK_INCOHERENT == 0 ||                                  \
+        MDBX_CPU_WRITEBACK_INCOHERENT == 1)
+#error MDBX_CPU_WRITEBACK_INCOHERENT must be defined as 0 or 1
 #endif /* MDBX_CPU_WRITEBACK_INCOHERENT */

 #ifndef MDBX_MMAP_INCOHERENT_FILE_WRITE
@@ -339,6 +373,9 @@
 #else
 #define MDBX_MMAP_INCOHERENT_FILE_WRITE 0
 #endif
+#elif !(MDBX_MMAP_INCOHERENT_FILE_WRITE == 0 ||                                \
+        MDBX_MMAP_INCOHERENT_FILE_WRITE == 1)
+#error MDBX_MMAP_INCOHERENT_FILE_WRITE must be defined as 0 or 1
 #endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */

 #ifndef MDBX_MMAP_INCOHERENT_CPU_CACHE
@@ -351,8 +388,21 @@
 /* LY: assume no relevant mmap/dcache issues. */
 #define MDBX_MMAP_INCOHERENT_CPU_CACHE 0
 #endif
+#elif !(MDBX_MMAP_INCOHERENT_CPU_CACHE == 0 ||                                 \
+        MDBX_MMAP_INCOHERENT_CPU_CACHE == 1)
+#error MDBX_MMAP_INCOHERENT_CPU_CACHE must be defined as 0 or 1
 #endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */

+#ifndef MDBX_MMAP_USE_MS_ASYNC
+#if MDBX_MMAP_INCOHERENT_FILE_WRITE || MDBX_MMAP_INCOHERENT_CPU_CACHE
+#define MDBX_MMAP_USE_MS_ASYNC 1
+#else
+#define MDBX_MMAP_USE_MS_ASYNC 0
+#endif
+#elif !(MDBX_MMAP_USE_MS_ASYNC == 0 || MDBX_MMAP_USE_MS_ASYNC == 1)
+#error MDBX_MMAP_USE_MS_ASYNC must be defined as 0 or 1
+#endif /* MDBX_MMAP_USE_MS_ASYNC */
+
 #ifndef MDBX_64BIT_ATOMIC
 #if MDBX_WORDBITS >= 64 || defined(DOXYGEN)
 #define MDBX_64BIT_ATOMIC 1
@@ -360,6 +410,8 @@
 #define MDBX_64BIT_ATOMIC 0
 #endif
 #define MDBX_64BIT_ATOMIC_CONFIG "AUTO=" MDBX_STRINGIFY(MDBX_64BIT_ATOMIC)
+#elif !(MDBX_64BIT_ATOMIC == 0 || MDBX_64BIT_ATOMIC == 1)
+#error MDBX_64BIT_ATOMIC must be defined as 0 or 1
 #else
 #define MDBX_64BIT_ATOMIC_CONFIG MDBX_STRINGIFY(MDBX_64BIT_ATOMIC)
 #endif /* MDBX_64BIT_ATOMIC */
@@ -385,6 +437,8 @@
 #endif
 #elif defined(_MSC_VER) || defined(__APPLE__) || defined(DOXYGEN)
 #define MDBX_64BIT_CAS 1
+#elif !(MDBX_64BIT_CAS == 0 || MDBX_64BIT_CAS == 1)
+#error MDBX_64BIT_CAS must be defined as 0 or 1
 #else
 #define MDBX_64BIT_CAS MDBX_64BIT_ATOMIC
 #endif
--- a/src/osal.c
+++ b/src/osal.c
--- a/src/osal.h
+++ b/src/osal.h
@@ -1,7 +1,7 @@
 /* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */

 /*
- * Copyright 2015-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2015-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -211,7 +211,8 @@ typedef pthread_mutex_t osal_fastmutex_t;
 /* OS abstraction layer stuff */

 MDBX_INTERNAL_VAR unsigned sys_pagesize;
-MDBX_MAYBE_UNUSED MDBX_INTERNAL_VAR unsigned sys_allocation_granularity;
+MDBX_MAYBE_UNUSED MDBX_INTERNAL_VAR unsigned sys_pagesize_ln2,
+    sys_allocation_granularity;

 /* Get the size of a memory page for the system.
 * This is the basic size that the platform's memory manager uses, and is
@@ -224,14 +225,15 @@ osal_syspagesize(void) {

 #if defined(_WIN32) || defined(_WIN64)
 typedef wchar_t pathchar_t;
+#define MDBX_PRIsPATH "ls"
 #else
 typedef char pathchar_t;
+#define MDBX_PRIsPATH "s"
 #endif

-typedef struct osal_mmap_param {
+typedef struct osal_mmap {
  union {
-    void *address;
-    uint8_t *dxb;
+    void *base;
    struct MDBX_lockinfo *lck;
  };
  mdbx_filehandle_t fd;
@@ -313,13 +315,12 @@ typedef struct osal_ioring {
  unsigned slots_left;
  unsigned allocated;
 #if defined(_WIN32) || defined(_WIN64)
-#define IOR_DIRECT 1
-#define IOR_OVERLAPPED 2
 #define IOR_STATE_LOCKED 1
+  HANDLE overlapped_fd;
  unsigned pagesize;
  unsigned last_sgvcnt;
  size_t last_bytes;
-  uint8_t flags, state, pagesize_ln2;
+  uint8_t direct, state, pagesize_ln2;
  unsigned event_stack;
  HANDLE *event_pool;
  volatile LONG async_waiting;
@@ -336,7 +337,6 @@ typedef struct osal_ioring {
 #define ior_last_sgvcnt(ior, item) (1)
 #define ior_last_bytes(ior, item) (item)->single.iov_len
 #endif /* !Windows */
-  mdbx_filehandle_t fd;
  ior_item_t *last;
  ior_item_t *pool;
  char *boundary;
@@ -345,11 +345,13 @@ typedef struct osal_ioring {
 #ifndef __cplusplus

 /* Actually this is not ioring for now, but on the way. */
-MDBX_INTERNAL_FUNC int osal_ioring_create(osal_ioring_t *,
+MDBX_INTERNAL_FUNC int osal_ioring_create(osal_ioring_t *
 #if defined(_WIN32) || defined(_WIN64)
-                                          uint8_t flags,
+                                          ,
+                                          bool enable_direct,
+                                          mdbx_filehandle_t overlapped_fd
 #endif /* Windows */
-                                          mdbx_filehandle_t fd);
+);
 MDBX_INTERNAL_FUNC int osal_ioring_resize(osal_ioring_t *, size_t items);
 MDBX_INTERNAL_FUNC void osal_ioring_destroy(osal_ioring_t *);
 MDBX_INTERNAL_FUNC void osal_ioring_reset(osal_ioring_t *);
@@ -360,7 +362,7 @@ typedef struct osal_ioring_write_result {
  unsigned wops;
 } osal_ioring_write_result_t;
 MDBX_INTERNAL_FUNC osal_ioring_write_result_t
-osal_ioring_write(osal_ioring_t *ior);
+osal_ioring_write(osal_ioring_t *ior, mdbx_filehandle_t fd);

 typedef struct iov_ctx iov_ctx_t;
 MDBX_INTERNAL_FUNC void osal_ioring_walk(
@@ -378,11 +380,13 @@ osal_ioring_used(const osal_ioring_t *ior) {
 }

 MDBX_MAYBE_UNUSED static inline int
-osal_ioring_reserve(osal_ioring_t *ior, size_t items, size_t bytes) {
+osal_ioring_prepare(osal_ioring_t *ior, size_t items, size_t bytes) {
  items = (items > 32) ? items : 32;
 #if defined(_WIN32) || defined(_WIN64)
-  const size_t npages = bytes >> ior->pagesize_ln2;
-  items = (items > npages) ? items : npages;
+  if (ior->direct) {
+    const size_t npages = bytes >> ior->pagesize_ln2;
+    items = (items > npages) ? items : npages;
+  }
 #else
  (void)bytes;
 #endif
@@ -522,9 +526,10 @@ MDBX_INTERNAL_FUNC int osal_thread_join(osal_thread_t thread);

 enum osal_syncmode_bits {
  MDBX_SYNC_NONE = 0,
-  MDBX_SYNC_DATA = 1,
-  MDBX_SYNC_SIZE = 2,
-  MDBX_SYNC_IODQ = 4
+  MDBX_SYNC_KICK = 1,
+  MDBX_SYNC_DATA = 2,
+  MDBX_SYNC_SIZE = 4,
+  MDBX_SYNC_IODQ = 8
 };

 MDBX_INTERNAL_FUNC int osal_fsync(mdbx_filehandle_t fd,
@@ -546,6 +551,19 @@ enum osal_openfile_purpose {
  MDBX_OPEN_DELETE
 };

+MDBX_MAYBE_UNUSED static __inline bool osal_isdirsep(pathchar_t c) {
+  return
+#if defined(_WIN32) || defined(_WIN64)
+      c == '\\' ||
+#endif
+      c == '/';
+}
+
+MDBX_INTERNAL_FUNC bool osal_pathequal(const pathchar_t *l, const pathchar_t *r,
+                                       size_t len);
+MDBX_INTERNAL_FUNC pathchar_t *osal_fileext(const pathchar_t *pathname,
+                                            size_t len);
+MDBX_INTERNAL_FUNC int osal_fileexists(const pathchar_t *pathname);
 MDBX_INTERNAL_FUNC int osal_openfile(const enum osal_openfile_purpose purpose,
                                     const MDBX_env *env,
                                     const pathchar_t *pathname,
@@ -559,9 +577,8 @@ MDBX_INTERNAL_FUNC int osal_lockfile(mdbx_filehandle_t fd, bool wait);

 #define MMAP_OPTION_TRUNCATE 1
 #define MMAP_OPTION_SEMAPHORE 2
-MDBX_INTERNAL_FUNC int osal_mmap(const int flags, osal_mmap_t *map,
-                                 const size_t must, const size_t limit,
-                                 const unsigned options);
+MDBX_INTERNAL_FUNC int osal_mmap(const int flags, osal_mmap_t *map, size_t size,
+                                 const size_t limit, const unsigned options);
 MDBX_INTERNAL_FUNC int osal_munmap(osal_mmap_t *map);
 #define MDBX_MRESIZE_MAY_MOVE 0x00000100
 #define MDBX_MRESIZE_MAY_UNMAP 0x00000200
@@ -583,6 +600,7 @@ MDBX_INTERNAL_FUNC int osal_msync(const osal_mmap_t *map, size_t offset,
 MDBX_INTERNAL_FUNC int osal_check_fs_rdonly(mdbx_filehandle_t handle,
                                            const pathchar_t *pathname,
                                            int err);
+MDBX_INTERNAL_FUNC int osal_check_fs_incore(mdbx_filehandle_t handle);

 MDBX_MAYBE_UNUSED static __inline uint32_t osal_getpid(void) {
  STATIC_ASSERT(sizeof(mdbx_pid_t) <= sizeof(uint32_t));
@@ -685,7 +703,7 @@ MDBX_INTERNAL_FUNC int osal_lck_destroy(MDBX_env *env,
 MDBX_INTERNAL_FUNC int osal_lck_seize(MDBX_env *env);

 /// \brief Downgrades the level of initially acquired lock to
-///   operational level specified by argument. The reson for such downgrade:
+///   operational level specified by argument. The reason for such downgrade:
 ///    - unblocking of other processes that are waiting for access, i.e.
 ///      if (env->me_flags & MDBX_EXCLUSIVE) != 0, then other processes
 ///      should be made aware that access is unavailable rather than
@@ -739,22 +757,7 @@ MDBX_INTERNAL_FUNC int osal_rpid_check(MDBX_env *env, uint32_t pid);

 #if defined(_WIN32) || defined(_WIN64)

-MDBX_INTERNAL_FUNC size_t osal_mb2w(wchar_t *dst, size_t dst_n, const char *src,
-                                    size_t src_n);
-
-#define OSAL_MB2WIDE(FROM, TO)                                                 \
-  do {                                                                         \
-    const char *const from_tmp = (FROM);                                       \
-    const size_t from_mblen = strlen(from_tmp);                                \
-    const size_t to_wlen = osal_mb2w(nullptr, 0, from_tmp, from_mblen);        \
-    if (to_wlen < 1 || to_wlen > /* MAX_PATH */ INT16_MAX)                     \
-      return ERROR_INVALID_NAME;                                               \
-    wchar_t *const to_tmp = _alloca((to_wlen + 1) * sizeof(wchar_t));          \
-    if (to_wlen + 1 !=                                                         \
-        osal_mb2w(to_tmp, to_wlen + 1, from_tmp, from_mblen + 1))              \
-      return ERROR_INVALID_NAME;                                               \
-    (TO) = to_tmp;                                                             \
-  } while (0)
+MDBX_INTERNAL_FUNC int osal_mb2w(const char *const src, wchar_t **const pdst);

 typedef void(WINAPI *osal_srwlock_t_function)(osal_srwlock_t *);
 MDBX_INTERNAL_VAR osal_srwlock_t_function osal_srwlock_Init,
@@ -886,6 +889,46 @@ MDBX_INTERNAL_VAR MDBX_SetFileIoOverlappedRange mdbx_SetFileIoOverlappedRange;

 /*----------------------------------------------------------------------------*/

+MDBX_MAYBE_UNUSED MDBX_NOTHROW_PURE_FUNCTION static __always_inline uint64_t
+osal_bswap64(uint64_t v) {
+#if __GNUC_PREREQ(4, 4) || __CLANG_PREREQ(4, 0) ||                             \
+    __has_builtin(__builtin_bswap64)
+  return __builtin_bswap64(v);
+#elif defined(_MSC_VER) && !defined(__clang__)
+  return _byteswap_uint64(v);
+#elif defined(__bswap_64)
+  return __bswap_64(v);
+#elif defined(bswap_64)
+  return bswap_64(v);
+#else
+  return v << 56 | v >> 56 | ((v << 40) & UINT64_C(0x00ff000000000000)) |
+         ((v << 24) & UINT64_C(0x0000ff0000000000)) |
+         ((v << 8) & UINT64_C(0x000000ff00000000)) |
+         ((v >> 8) & UINT64_C(0x00000000ff000000)) |
+         ((v >> 24) & UINT64_C(0x0000000000ff0000)) |
+         ((v >> 40) & UINT64_C(0x000000000000ff00));
+#endif
+}
+
+MDBX_MAYBE_UNUSED MDBX_NOTHROW_PURE_FUNCTION static __always_inline uint32_t
+osal_bswap32(uint32_t v) {
+#if __GNUC_PREREQ(4, 4) || __CLANG_PREREQ(4, 0) ||                             \
+    __has_builtin(__builtin_bswap32)
+  return __builtin_bswap32(v);
+#elif defined(_MSC_VER) && !defined(__clang__)
+  return _byteswap_ulong(v);
+#elif defined(__bswap_32)
+  return __bswap_32(v);
+#elif defined(bswap_32)
+  return bswap_32(v);
+#else
+  return v << 24 | v >> 24 | ((v << 8) & UINT32_C(0x00ff0000)) |
+         ((v >> 8) & UINT32_C(0x0000ff00));
+#endif
+}
+
+/*----------------------------------------------------------------------------*/
+
 #if defined(_MSC_VER) && _MSC_VER >= 1900
 /* LY: MSVC 2015/2017/2019 has buggy/inconsistent PRIuPTR/PRIxPTR macros
 * for internal format-args checker. */
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -92,11 +92,13 @@ else()
    set_tests_properties(smoke_chk PROPERTIES
      DEPENDS smoke
      TIMEOUT 60
+      FAIL_REGULAR_EXPRESSION "cooperative mode"
      REQUIRED_FILES smoke.db)
    add_test(NAME smoke_chk_copy COMMAND ${MDBX_OUTPUT_DIR}/mdbx_chk -nvv smoke.db-copy)
    set_tests_properties(smoke_chk_copy PROPERTIES
      DEPENDS smoke
      TIMEOUT 60
+      FAIL_REGULAR_EXPRESSION "cooperative mode"
      REQUIRED_FILES smoke.db-copy)
  endif()

@@ -109,15 +111,16 @@ else()
    TIMEOUT 600
    RUN_SERIAL OFF)
  if(MDBX_BUILD_TOOLS)
-    add_test(NAME dupsort_writemap_chk COMMAND ${MDBX_OUTPUT_DIR}/mdbx_chk -nvv dupsort_writemap.db)
+    add_test(NAME dupsort_writemap_chk COMMAND ${MDBX_OUTPUT_DIR}/mdbx_chk -nvvwc dupsort_writemap.db)
    set_tests_properties(dupsort_writemap_chk PROPERTIES
      DEPENDS dupsort_writemap
      TIMEOUT 60
      REQUIRED_FILES dupsort_writemap.db)
-    add_test(NAME dupsort_writemap_chk_copy COMMAND ${MDBX_OUTPUT_DIR}/mdbx_chk -nvv dupsort_writemap.db-copy)
+    add_test(NAME dupsort_writemap_chk_copy COMMAND ${MDBX_OUTPUT_DIR}/mdbx_chk -nvvc dupsort_writemap.db-copy)
    set_tests_properties(dupsort_writemap_chk_copy PROPERTIES
      DEPENDS dupsort_writemap
      TIMEOUT 60
+      FAIL_REGULAR_EXPRESSION "monopolistic mode"
      REQUIRED_FILES dupsort_writemap.db-copy)
  endif()

@@ -128,15 +131,17 @@ else()
    TIMEOUT 1800
    RUN_SERIAL OFF)
  if(MDBX_BUILD_TOOLS)
-    add_test(NAME uniq_nested_chk COMMAND ${MDBX_OUTPUT_DIR}/mdbx_chk -nvv uniq_nested.db)
+    add_test(NAME uniq_nested_chk COMMAND ${MDBX_OUTPUT_DIR}/mdbx_chk -nvvw uniq_nested.db)
    set_tests_properties(uniq_nested_chk PROPERTIES
      DEPENDS uniq_nested
      TIMEOUT 60
+      FAIL_REGULAR_EXPRESSION "cooperative mode"
      REQUIRED_FILES uniq_nested.db)
    add_test(NAME uniq_nested_chk_copy COMMAND ${MDBX_OUTPUT_DIR}/mdbx_chk -nvv uniq_nested.db-copy)
    set_tests_properties(uniq_nested_chk_copy PROPERTIES
      DEPENDS uniq_nested
      TIMEOUT 60
+      FAIL_REGULAR_EXPRESSION "cooperative mode"
      REQUIRED_FILES uniq_nested.db-copy)
  endif()

--- a/test/append.c++
+++ b/test/append.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -21,7 +21,14 @@ public:
  bool run() override;

  static bool review_params(actor_params &params) {
-    return testcase::review_params(params) && params.make_keygen_linear();
+    if (!testcase::review_params(params))
+      return false;
+    const bool ordered = !flipcoin_x3();
+    log_notice("the '%s' key-generation mode is selected",
+               ordered ? "ordered/linear" : "unordered/non-linear");
+    if (ordered && !params.make_keygen_linear())
+      return false;
+    return true;
  }
 };
 REGISTER_TESTCASE(append);
@@ -133,8 +140,6 @@ bool testcase_append::run() {
        }
      } else
        failure_perror("mdbx_get_equal_or_great()", err);
-
-      assert(!expect_key_mismatch);
    }

    err = mdbx_cursor_put(cursor_guard.get(), &key->value, &data->value, flags);
@@ -148,12 +153,25 @@ bool testcase_append::run() {

    if (!expect_key_mismatch) {
      if (unlikely(err != MDBX_SUCCESS))
-        failure_perror("mdbx_cursor_put(insert-a)", err);
+        failure_perror("mdbx_cursor_put(append)", err);
      ++inserted_number;
      inserted_checksum.push((uint32_t)inserted_number, key->value);
      inserted_checksum.push(10639, data->value);
+
+      if (config.params.speculum) {
+        Item item(iov2dataview(key), iov2dataview(data));
+        const auto insertion_result = speculum.insert(item);
+        if (!insertion_result.second) {
+          char dump_key[32], dump_value[32];
+          log_error(
+              "speculum.append: unexpected %s {%s, %s}", "MDBX_SUCCESS",
+              mdbx_dump_val(&key->value, dump_key, sizeof(dump_key)),
+              mdbx_dump_val(&data->value, dump_value, sizeof(dump_value)));
+          return false;
+        }
+      }
    } else if (unlikely(err != MDBX_EKEYMISMATCH))
-      failure_perror("mdbx_cursor_put(insert-a) != MDBX_EKEYMISMATCH", err);
+      failure_perror("mdbx_cursor_put(append) != MDBX_EKEYMISMATCH", err);

    if (++txn_nops >= config.params.batch_write) {
      err = breakable_restart();
@@ -166,6 +184,10 @@ bool testcase_append::run() {
      committed_inserted_number = inserted_number;
      committed_inserted_checksum = inserted_checksum;
      txn_nops = 0;
+      if (!speculum_verify()) {
+        log_notice("append: bailout breakable_restart");
+        return false;
+      }
    }

    report(1);
@@ -181,6 +203,10 @@ bool testcase_append::run() {
  }
  //----------------------------------------------------------------------------
  txn_begin(true);
+  if (!speculum_verify()) {
+    log_notice("append: bailout verify");
+    return false;
+  }
  cursor_renew();

  MDBX_val check_key, check_data;
@@ -209,7 +235,8 @@ bool testcase_append::run() {
    failure("read_count(%" PRIu64 ") != inserted_number(%" PRIu64 ")",
            read_count, inserted_number);

-  if (unlikely(read_checksum.value != inserted_checksum.value))
+  if (unlikely(read_checksum.value != inserted_checksum.value) &&
+      !keyvalue_maker.is_unordered())
    failure("read_checksum(0x%016" PRIu64 ") "
            "!= inserted_checksum(0x%016" PRIu64 ")",
            read_checksum.value, inserted_checksum.value);
--- a/test/base.h++
+++ b/test/base.h++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -30,6 +30,10 @@
 #define _WIN32_WINNT 0x0601 /* Windows 7 */
 #endif
 #ifdef _MSC_VER
+/* Workaround for MSVC' header `extern "C"` vs `std::` redefinition bug */
+#if defined(__SANITIZE_ADDRESS__) && !defined(_DISABLE_VECTOR_ANNOTATION)
+#define _DISABLE_VECTOR_ANNOTATION
+#endif /* _DISABLE_VECTOR_ANNOTATION */
 #ifndef _CRT_SECURE_NO_WARNINGS
 #define _CRT_SECURE_NO_WARNINGS
 #endif /* _CRT_SECURE_NO_WARNINGS */
--- a/test/cases.c++
+++ b/test/cases.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/chrono.c++
+++ b/test/chrono.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -87,10 +87,11 @@ time from_ms(uint64_t ms) {
 time now_realtime() {
 #if defined(_WIN32) || defined(_WIN64) || defined(_WINDOWS)
  static void(WINAPI * query_time)(LPFILETIME);
-  if (!query_time) {
-    query_time = (void(WINAPI *)(LPFILETIME))GetProcAddress(
-        GetModuleHandle(TEXT("kernel32.dll")),
-        "GetSystemTimePreciseAsFileTime");
+  if (unlikely(!query_time)) {
+    HMODULE hModule = GetModuleHandle(TEXT("kernel32.dll"));
+    if (hModule)
+      query_time = (void(WINAPI *)(LPFILETIME))GetProcAddress(
+          hModule, "GetSystemTimePreciseAsFileTime");
    if (!query_time)
      query_time = GetSystemTimeAsFileTime;
  }
--- a/test/chrono.h++
+++ b/test/chrono.h++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/config.c++
+++ b/test/config.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/config.h++
+++ b/test/config.h++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/dead.c++
+++ b/test/dead.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/hill.c++
+++ b/test/hill.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/jitter.c++
+++ b/test/jitter.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/keygen.c++
+++ b/test/keygen.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -227,7 +227,8 @@ void maker::setup(const config::actor_params_pod &actor, unsigned actor_id,

  (void)thread_number;
  mapping = actor.keygen;
-  salt = (actor.keygen.seed + actor_id) * UINT64_C(14653293970879851569);
+  salt =
+      (actor.keygen.seed + uint64_t(actor_id)) * UINT64_C(14653293970879851569);

  base = actor.serial_base();
 }
@@ -315,11 +316,12 @@ void __hot maker::mk_begin(const serial_t serial, const essentials &params,
  out.value.iov_len = std::max(unsigned(params.minlen), length(serial));
  const auto variation = params.maxlen - params.minlen;
  if (variation) {
-    if (serial % (variation + 1)) {
+    if (serial % (variation + serial_t(1))) {
      auto refix = serial * UINT64_C(48835288005252737);
      refix ^= refix >> 32;
-      out.value.iov_len = std::max(
-          out.value.iov_len, params.minlen + 1 + size_t(refix) % variation);
+      out.value.iov_len =
+          std::max(out.value.iov_len,
+                   params.minlen + size_t(1) + size_t(refix) % variation);
    }
  }

--- a/test/keygen.h++
+++ b/test/keygen.h++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/log.c++
+++ b/test/log.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -142,7 +142,7 @@ void output_nocheckloglevel_ap(const logging::loglevel priority,
          prefix.c_str(), level2str(priority), suffix.c_str());

  va_list ones;
-  memset(&ones, 0, sizeof(ones)) /* zap MSVC and other stupid compilers */;
+  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);
@@ -153,11 +153,11 @@ void output_nocheckloglevel_ap(const logging::loglevel priority,
  switch (end) {
  default:
    putc('\n', last);
-  // fall through
+    MDBX_CXX17_FALLTHROUGH; // fall through
  case '\n':
    fflush(last);
    last = nullptr;
-  // fall through
+    MDBX_CXX17_FALLTHROUGH; // fall through
  case ' ':
  case '_':
  case ':':
--- a/test/log.h++
+++ b/test/log.h++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/long_stochastic.sh
+++ b/test/long_stochastic.sh
@@ -12,6 +12,7 @@ UNAME="$(uname -s 2>/dev/null || echo Unknown)"
 DB_UPTO_MB=17408
 PAGESIZE=min
 DONT_CHECK_RAM=no
+EXTRA=no

 while [ -n "$1" ]
 do
@@ -31,8 +32,9 @@ do
    echo "--dir PATH             Specifies directory for test DB and other files (it will be cleared)"
    echo "--db-upto-mb NN        Limits upper size of test DB to the NN megabytes"
    echo "--no-geometry-jitter   Disable jitter for geometry upper-size"
-    echo "--pagesize NN          Use specified page size (256 is minimal and used by default) "
-    echo "--dont-check-ram-size  Don't check available RAM "
+    echo "--pagesize NN          Use specified page size (256 is minimal and used by default)"
+    echo "--dont-check-ram-size  Don't check available RAM"
+    echo "--extra                Iterate extra modes/flags"
    echo "--help                 Print this usage help and exit"
    exit -2
  ;;
@@ -136,7 +138,7 @@ do
        PAGESIZE=$((1024*64))
      ;;
      *)
-        echo "Invalig page size '$2'"
+        echo "Invalid page size '$2'"
        exit -2
      ;;
    esac
@@ -145,6 +147,9 @@ do
  --dont-check-ram-size)
    DONT_CHECK_RAM=yes
  ;;
+  --extra)
+    EXTRA=yes
+  ;;
  *)
    echo "Unknown option '$1'"
    exit -2
@@ -350,9 +355,12 @@ else
  }
 fi

-syncmodes=("" ,+nosync-safe ,+nosync-utterly)
-options=(writemap lifo notls perturb)
-
+if [ "$EXTRA" != "no" ]; then
+  options=(writemap lifo notls perturb nomeminit nordahead)
+else
+  options=(writemap lifo notls)
+fi
+syncmodes=("" ,+nosync-safe ,+nosync-utterly ,+nometasync)
 function join { local IFS="$1"; shift; echo "$*"; }

 function bits2options {
@@ -414,65 +422,89 @@ 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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
        --keygen.seed=${seed}

      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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
        --keygen.seed=${seed}

      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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
        --keygen.seed=${seed}

+      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 \
+          --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 \
+          --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 \
+          --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 \
+          --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 \
+          --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
+          --keygen.seed=${seed}
+      fi
+
      split=4
      caption="Probe #$((++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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --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 \
-        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%3]} \
+        --nops=$nops --batch.write=$wbatch --mode=$(bits2options $bits)${syncmodes[count%4]} \
        --keygen.seed=${seed}
    done # options
    loop=$((loop + 1))
--- a/test/main.c++
+++ b/test/main.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -129,8 +129,7 @@ void actor_params::set_defaults(const std::string &tmpdir) {
 #endif

  pathname_db = tmpdir + "mdbx-test.db";
-  mode_flags = MDBX_NOSUBDIR | MDBX_WRITEMAP | MDBX_SAFE_NOSYNC |
-               MDBX_NOMEMINIT | MDBX_COALESCE | MDBX_LIFORECLAIM | MDBX_ACCEDE;
+  mode_flags = MDBX_NOSUBDIR | MDBX_WRITEMAP | MDBX_SYNC_DURABLE | MDBX_ACCEDE;
  table_flags = MDBX_DUPSORT;

  size_lower = -1;
--- a/test/nested.c++
+++ b/test/nested.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/osal-unix.c++
+++ b/test/osal-unix.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/osal-windows.c++
+++ b/test/osal-windows.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -248,7 +248,7 @@ Environment:
    CommandLine.push_back('"');

    for (auto It = Argument.begin();; ++It) {
-      unsigned NumberBackslashes = 0;
+      size_t NumberBackslashes = 0;

      while (It != Argument.end() && *It == '\\') {
        ++It;
@@ -435,7 +435,7 @@ void osal_udelay(size_t us) {
    unsigned timeslice_ms = 1;
    while (timeBeginPeriod(timeslice_ms) == TIMERR_NOCANDO)
      ++timeslice_ms;
-    threshold_us = timeslice_ms * 1500u;
+    threshold_us = timeslice_ms * size_t(1500);
    assert(threshold_us > 0);
  }

--- a/test/osal.h++
+++ b/test/osal.h++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/pcrf/pcrf_test.c
+++ b/test/pcrf/pcrf_test.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2022 Leonid Yuriev <leo@yuriev.ru>.
+ * Copyright 2016-2023 Leonid Yuriev <leo@yuriev.ru>.
 * Copyright 2015 Vladimir Romanov
 * <https://www.linkedin.com/in/vladimirromanov>, Yota Lab.
 *
--- a/test/test.c++
+++ b/test/test.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -100,7 +100,7 @@ int testcase::hsr_callback(const MDBX_env *env, const MDBX_txn *txn,
       info.mi_geo.current >= info.mi_geo.upper)) {
    osal_yield();
    if (retry > 0)
-      osal_udelay(retry * 100);
+      osal_udelay(retry * size_t(100));
    return MDBX_RESULT_FALSE /* retry / wait until reader done */;
  }

@@ -158,12 +158,17 @@ void testcase::db_open() {
  if (config.params.random_writemap && flipcoin())
    mode ^= MDBX_WRITEMAP;

-  actual_env_mode = mode;
  int rc = mdbx_env_open(db_guard.get(), config.params.pathname_db.c_str(),
                         mode, 0640);
  if (unlikely(rc != MDBX_SUCCESS))
    failure_perror("mdbx_env_open()", rc);

+  unsigned env_flags_proxy;
+  rc = mdbx_env_get_flags(db_guard.get(), &env_flags_proxy);
+  if (unlikely(rc != MDBX_SUCCESS))
+    failure_perror("mdbx_env_get_flags()", rc);
+  actual_env_mode = MDBX_env_flags_t(env_flags_proxy);
+
  rc = mdbx_env_set_syncperiod(db_guard.get(), unsigned(0.042 * 65536));
  if (unlikely(rc != MDBX_SUCCESS) && rc != MDBX_BUSY)
    failure_perror("mdbx_env_set_syncperiod()", rc);
--- a/test/test.h++
+++ b/test/test.h++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
@@ -101,10 +101,10 @@ class testcase;

 class registry {
  struct record {
-    actor_testcase id;
+    actor_testcase id = ac_none;
    std::string name;
-    bool (*review_params)(actor_params &);
-    testcase *(*constructor)(const actor_config &, const mdbx_pid_t);
+    bool (*review_params)(actor_params &) = nullptr;
+    testcase *(*constructor)(const actor_config &, const mdbx_pid_t) = nullptr;
  };
  std::unordered_map<std::string, const record *> name2id;
  std::unordered_map<int, const record *> id2record;
--- a/test/ttl.c++
+++ b/test/ttl.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/utils.c++
+++ b/test/utils.c++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/utils.h++
+++ b/test/utils.h++
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 Leonid Yuriev <leo@yuriev.ru>
+ * Copyright 2017-2023 Leonid Yuriev <leo@yuriev.ru>
 * and other libmdbx authors: please see AUTHORS file.
 * All rights reserved.
 *
--- a/test/valgrind_suppress.txt
+++ b/test/valgrind_suppress.txt
@@ -30,8 +30,24 @@
   ...
   fun:wipe_steady*
 }
+{
+   msync-meta
+   Memcheck:Param
+   msync(start)
+   fun:msync
+   ...
+   fun:meta_sync*
+}
+{
+   msync-spill
+   Memcheck:Param
+   msync(start)
+   fun:msync
+   ...
+   fun:txn_spill*
+}

-# memcmp() inside iov_write() as workaround for https://web.archive.org/web/https://github.com/erthink/libmdbx/issues/269
+# memcmp() inside iov_write() as workaround for https://libmdbx.dqdkfa.ru/dead-github/issues/269
 {
   iov-pagecheck-1
   Memcheck:Cond