The planned frontward release with new superior features on the day of 20 anniversary of [Positive Technologies](https://ptsecurty.com).
New:
----
- The `Big Foot` feature which significantly reduces GC overhead for processing large lists of retired pages from huge transactions.
Now _libmdbx_ avoid creating large chunks of PNLs (page number lists) which required a long sequences of free pages, aka large/overflow pages.
Thus avoiding searching, allocating and storing such sequences inside GC.
- Improved hot/online validation and checking of database pages both for more robustness and performance.
- New solid and fast method to latch meta-pages called `Troika`.
The minimum of memory barriers, reads, comparisons and conditional transitions are used.
- New `MDBX_VALIDATION` environment options to extra validation of DB structure and pages content for carefully/safe handling damaged or untrusted DB.
- Accelerated ×16/×8/×4 by AVX512/AVX2/SSE2/Neon implementations of search page sequences.
- Added the `gcrtime_seconds16dot16` counter to the "Page Operation Statistics" that accumulates time spent for GC searching and reclaiming.
- Copy-with-compactification now clears/zeroes unused gaps inside database pages.
- The `C` and `C++` APIs has been extended and/or refined to simplify using `wchar_t` pathnames.
On Windows the `mdbx_env_openW()`, `mdbx_env_get_pathW()`, `mdbx_env_copyW()`, `mdbx_env_open_for_recoveryW()` are available for now,
but the `mdbx_env_get_path()` has been replaced in favor of `mdbx_env_get_pathW()`.
- Added explicit error message for Buildroot's Microblaze toolchain maintainers.
- Added `MDBX_MANAGE_BUILD_FLAGS` build options for CMake.
- Speed-up internal `bsearch`/`lower_bound` implementation using branchless tactic, including workaround for CLANG x86 optimiser bug.
- A lot internal refinement and micro-optimisations.
- Internally counted volume of dirty pages (unused for now but for coming features).
Fixes:
------
- Never use modern `__cxa_thread_atexit()` on Apple's OSes.
- Don't check owner for finished transactions.
- Fixed typo in `MDBX_EINVAL` which breaks MingGW builds with CLANG.
37 files changed, 7604 insertions(+), 7417 deletions(-)
Signed-off-by: Леонид Юрьев (Leonid Yuriev) <leo@yuriev.ru>
The stable bugfix release.
It is planned that this will be the last release of the v0.11 branch.
New:
----
- The C++ API has been refined to simplify support for `wchar_t` in path names.
- Added explicit error message for Buildroot's Microblaze toolchain maintainers.
Fixes:
------
- Never use modern `__cxa_thread_atexit()` on Apple's OSes.
- Use `MultiByteToWideChar(CP_THREAD_ACP)` instead of `mbstowcs()`.
- Don't check owner for finished transactions.
- Fixed typo in `MDBX_EINVAL` which breaks MingGW builds with CLANG.
Minors:
-------
- Fixed variable name typo.
- Using `ldd` to check used dso.
- Added `MDBX_WEAK_IMPORT_ATTRIBUTE` macro.
- Use current transaction geometry for untouched parameters when `env_set_geometry()` called within a write transaction.
- Minor clarified `iov_page()` failure case.
14 files changed, 263 insertions(+), 252 deletions(-)
Signed-off-by: Леонид Юрьев (Leonid Yuriev) <leo@yuriev.ru>
Устранение крайне маловероятного регресса после перехода на мета-тройку:
- процесс А открыает БД и читает мета-траницы для формирования тройки;
- процесс Б постоянно коммитит новые транзакции;
- есть шанс что процесс А при чтении разных мета страниц попадет на момент их обновления более одного раза,
это может привести к ложной ошибке коллизии мета-страниц,
так как для обновляемых мета-страниц будет виден нулевой номер транзакции.
The stable bugfix release.
It is planned that this will be the last release of the v0.11 branch.
Acknowledgements:
-----------------
- [Alex Sharov](https://github.com/AskAlexSharov) and Erigon team for reporting and testing.
- [Andrew Ashikhmin](https://gitflic.ru/user/yperbasis) for contributing.
New:
----
- Ability to customise `MDBX_LOCK_SUFFIX`, `MDBX_DATANAME`, `MDBX_LOCKNAME` just by predefine ones during build.
- Added to [`mdbx::env_managed`](https://libmdbx.dqdkfa.ru/group__cxx__api.html#classmdbx_1_1env__managed)'s methods a few overloads with `const char* pathname` parameter (C++ API).
Fixes:
------
- Fixed hang copy-with-compactification of a corrupted DB
or in case the volume of output pages is a multiple of `MDBX_ENVCOPY_WRITEBUF`.
- Fixed standalone non-CMake build on MacOS (`#include AvailabilityMacros.h>`).
- Fixed unexpected `MDBX_PAGE_FULL` error in rare cases with large database page sizes.
Minors:
-------
- Minor fixes Doxygen references, comments, descriptions, etc.
- Fixed copy&paste typo inside `meta_checktxnid()`.
- Minor fix `meta_checktxnid()` to avoid assertion in debug mode.
- Minor fix `mdbx_env_set_geometry()` to avoid returning `EINVAL` in particular rare cases.
- Minor refine/fix batch-get testcase for large page size.
- Added `--pagesize NN` option to long-stotastic test script.
- Updated Valgrind-suppressions file for modern GCC.
- Fixed `has no symbols` warning from Apple's ranlib.
18 files changed, 318 insertions(+), 178 deletions(-)
Signed-off-by: Леонид Юрьев (Leonid Yuriev) <leo@yuriev.ru>
1. Explicitly check and handle a race/collision case with `find_oldest_reader()`.
2. Handle "recovery mode" (me_stuck_meta >= 0) by the same code as for regular latch.
3. Add bailout error message for buggy compiler and/or hardware (paranoid).
1. Fix regression `assert: oldest >= lck->mti_oldest_reader.weak` after d4bf0a3332.
2. Add explicit check, kick and notice for stuck reader.
3. Made more e2k-frendly.
Кроме небольшого рефакторинга здесь реализуется более регулярный способ
обхода дерева при копировании с компактификаций. В частности, полная
инициализация курсоров позволяет выполнять больше проверок/контроля
структуры БД и избавиться от флажка CC_COPYING.
Beside a small refactoring, a more regular way of traversing the tree
when copying with compactification is implemented here. In particular,
full initialization of cursors allows to perform more checks/control of
the DB structure and get rid of the CC_COPYING flag.
Здесь основная часть изменений преобразующих отладочную проверку страниц
в регулярный и доступный пользователю осторожный/безопасный режим работы
с потенциально поврежденной БД.
Here the major part of the changes that transform a debugging check of
pages into a regular and user-accessible careful/safe mode for working
with a potentially corrupted database.
Chunking long list of retired pages during huge transactions commit
to avoid use sequences of pages:
- splits a long retired page-number-list into chunks
which fits one per single overflow/large page;
- this requires a few unique id for keys
for create such records into GC/freeDB;
- just use the necessary subsequent IDs following the current
transaction ID and then take the last of ones to update a meta-page.
Thus avoids using/allocating/searching a sequence of free pages
but just increase txnid more than one during the commit
a huge write transaction with a long retired-pages-list.
The stable release with an important fixes and workaround for the critical macOS thread-local-storage issue.
Acknowledgements:
-----------------
- [Masatoshi Fukunaga](https://github.com/mah0x211) for [Lua bindings](https://github.com/mah0x211/lua-libmdbx).
New:
----
- Added most of transactions flags to the public API.
- Added `MDBX_NOSUCCESS_EMPTY_COMMIT` build option to return non-success result (`MDBX_RESULT_TRUE`) on empty commit.
- Reworked validation and import of DBI-handles into a transaction.
Assumes these changes will be invisible to most users, but will cause fewer surprises in complex DBI cases.
- Added ability to open DB in without-LCK (exclusive read-only) mode in case no permissions to create/write LCK-file.
Fixes:
------
- A series of fixes and improvements for automatically generated documentation (Doxygen).
- Fixed copy&paste bug with could lead to `SIGSEGV` (nullptr dereference) in the exclusive/no-lck mode.
- Fixed minor warnings from modern Apple's CLANG 13.
- Fixed minor warnings from CLANG 14 and in-development CLANG 15.
- Fixed `SIGSEGV` regression in without-LCK (exclusive read-only) mode.
- Fixed `mdbx_check_fs_local()` for CDROM case on Windows.
- Fixed nasty typo of typename which caused false `MDBX_CORRUPTED` error in a rare execution path,
when the size of the thread-ID type not equal to 8.
- Fixed write-after-free memory corruption on latest `macOS` during finalization/cleanup of thread(s) that executed read transaction(s).
> The issue was suddenly discovered by a [CI](https://en.wikipedia.org/wiki/Continuous_integration)
> after adding an iteration with macOS 11 "Big Sur", and then reproduced on recent release of macOS 12 "Monterey".
> The issue was never noticed nor reported on macOS 10 "Catalina" nor others.
> Analysis shown that the problem caused by a change in the behavior of the system library (internals of dyld and pthread)
> during thread finalization/cleanup: now a memory allocated for a `__thread` variable(s) is released
> before execution of the registered Thread-Local-Storage destructor(s),
> thus a TLS-destructor will write-after-free just by legitime dereference any `__thread` variable.
> This is unexpected crazy-like behavior since the order of resources releasing/destroying
> is not the reverse of ones acquiring/construction order. Nonetheless such surprise
> is now workarounded by using atomic compare-and-swap operations on a 64-bit signatures/cookies.
- Fixed Elbrus/E2K LCC 1.26 compiler warnings (memory model for atomic operations, etc).
Minors:
-------
- Refined `release-assets` GNU Make target.
- Added logging to `mdbx_fetch_sdb()` to help debugging complex DBI-handels use cases.
- Added explicit error message from probe of no-support for `std::filesystem`.
- Added contributors "score" table by `git fame` to generated docs.
- Added `mdbx_assert_fail()` to public API (mostly for backtracing).
- Now C++20 concepts used/enabled only when `__cpp_lib_concepts >= 202002`.
- Don't provide nor report package information if used as a CMake subproject.
Signed-off-by: Леонид Юрьев (Leonid Yuriev) <leo@yuriev.ru>
