f4d75452fc
Apparently, invoking fcntl(fd, F_SETFL, O_DIRECT) will lead to unexpected behaviour on Linux bcachefs and possibly other file systems, depending on the operating system version. So, let us avoid doing that, and instead just attempt to pass the O_DIRECT flag to open(). This should make us compatible with NetBSD, IBM AIX, as well as Solaris and its derivatives. We will only implement innodb_log_file_buffering=OFF on systems where we can determine the physical block size (typically 512 or 4096 bytes). Currently, those operating systems are Linux and Microsoft Windows. HAVE_FCNTL_DIRECT, os_file_set_nocache(): Remove. OS_FILE_OVERWRITE, OS_FILE_CREATE_PATH: Remove (never used parameters). os_file_log_buffered(), os_file_log_maybe_unbuffered(): Helper functions. os_file_create_func(): When applicable, initially attempt to open files in O_DIRECT mode. For type==OS_LOG_FILE && create_mode != OS_FILE_CREATE we will first invoke stat(2) on the file name to find out if the size is compatible with O_DIRECT. If create_mode == OS_FILE_CREATE, we will invoke fstat(2) on the created log file afterwards, and may close and reopen the file in O_DIRECT mode if applicable. create_temp_file(): Support O_DIRECT. This is only used if O_TMPFILE is available and innodb_disable_sort_file_cache=ON (non-default value). Notably, that setting never worked on Microsoft Windows. row_merge_file_create_mode(): Split from row_merge_file_create_low(). Create a temporary file in the specified mode. Reviewed by: Vladislav Vaintroub
Code status:
ci.appveyor.com
MariaDB: The open source relational 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/
Help
More help is available from the Maria Discuss mailing list https://launchpad.net/~maria-discuss, MariaDB's Zulip instance, https://mariadb.zulipchat.com/
Live QA for beginner contributors
MariaDB has a dedicated time each week when we answer new contributor questions live on Zulip. From 8:00 to 10:00 UTC on Mondays, and 10:00 to 12:00 UTC on Thursdays, anyone can ask any questions they’d like, and a live developer will be available to assist.
New contributors can ask questions any time, but we will provide immediate feedback during that interval.
Licensing
NOTE:
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