52c29f3bdc
Heap tables are allocated blocks to store rows according to my_default_record_cache (mapped to the server global variable read_buffer_size). This causes performance issues when the record length is big (> 1000 bytes) and the my_default_record_cache is small. Changed to instead split the default heap allocation to 1/16 of the allowed space and not use my_default_record_cache anymore when creating the heap. The allocation is also aligned to be just under a power of 2. For some test that I have been running, which was using record length=633, the speed of the query doubled thanks to this change. Other things: - Fixed calculation of max_records passed to hp_create() to take into account padding between records. - Updated calculation of memory needed by heap tables. Before we did not take into account internal structures needed to access rows. - Changed block sized for memory_table from 1 to 16384 to get less fragmentation. This also avoids a problem where we need 1K to manage index and row storage which was not counted for before. - Moved heap memory usage to a separate test for 32 bit. - Allocate all data blocks in heap in powers of 2. Change reported memory usage for heap to reflect this. Reviewed-by: Sergei Golubchik <serg@mariadb.org> |
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| BUILD | ||
| client | ||
| cmake | ||
| dbug | ||
| debian | ||
| Docs | ||
| extra | ||
| include | ||
| libmariadb@3f2196d84e | ||
| libmysqld | ||
| libservices | ||
| man | ||
| mysql-test | ||
| mysys | ||
| mysys_ssl | ||
| plugin | ||
| randgen/conf | ||
| scripts | ||
| sql | ||
| sql-bench | ||
| sql-common | ||
| storage | ||
| strings | ||
| support-files | ||
| tests | ||
| tpool | ||
| unittest | ||
| vio | ||
| win | ||
| wsrep-lib@70cd967f5e | ||
| zlib | ||
| .clang-format | ||
| .gitattributes | ||
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| .gitlab-ci.yml | ||
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| appveyor.yml | ||
| BUILD-CMAKE | ||
| CMakeLists.txt | ||
| config.h.cmake | ||
| configure.cmake | ||
| CONTRIBUTING.md | ||
| COPYING | ||
| CREDITS | ||
| INSTALL-SOURCE | ||
| INSTALL-WIN-SOURCE | ||
| KNOWN_BUGS.txt | ||
| README.md | ||
| THIRDPARTY | ||
| VERSION | ||
Code status:
ci.appveyor.com
MariaDB: The innovative open source database
MariaDB was designed as a drop-in replacement of MySQL(R) with more features, new storage engines, fewer bugs, and better performance.
MariaDB is brought to you by the MariaDB Foundation and the MariaDB Corporation. Please read the CREDITS file for details about the MariaDB Foundation, and who is developing MariaDB.
MariaDB is developed by many of the original developers of MySQL who now work for the MariaDB Corporation, the MariaDB Foundation and by many people in the community.
MySQL, which is the base of MariaDB, is a product and trademark of Oracle Corporation, Inc. For a list of developers and other contributors, see the Credits appendix. You can also run 'SHOW authors' to get a list of active contributors.
A description of the MariaDB project and a manual can be found at:
https://mariadb.com/kb/en/mariadb-vs-mysql-features/
https://mariadb.com/kb/en/mariadb-versus-mysql-compatibility/
https://mariadb.com/kb/en/new-and-old-releases/
Getting the code, building it and testing it
Refer to the following guide: https://mariadb.org/get-involved/getting-started-for-developers/get-code-build-test/ which outlines how to build the source code correctly and run the MariaDB testing framework, as well as which branch to target for your contributions.
Help
More help is available from the Maria Discuss mailing list https://lists.mariadb.org/postorius/lists/discuss.lists.mariadb.org/ and MariaDB's Zulip instance, https://mariadb.zulipchat.com/
Licensing
MariaDB is specifically available only under version 2 of the GNU General Public License (GPLv2). (I.e. Without the "any later version" clause.) This is inherited from MySQL. Please see the README file in the MySQL distribution for more information.
License information can be found in the COPYING file. Third party license information can be found in the THIRDPARTY file.
Bug Reports
Bug and/or error reports regarding MariaDB should be submitted at: https://jira.mariadb.org
For reporting security vulnerabilities see: https://mariadb.org/about/security-policy/
The code for MariaDB, including all revision history, can be found at: https://github.com/MariaDB/server