From: Date: October 1 2008 2:27pm Subject: bzr push into mysql-5.1 branch (davi:2692 to 2693) Bug#35164 Bug#37536 List-Archive: http://lists.mysql.com/commits/54923 X-Bug: 35164,37536 Message-Id: <20081001122746.28DC6EC41F@skynet.ctb.virtua.com.br> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit 2693 Davi Arnaut 2008-10-01 Bug#35164: Large number of invalid pthread_attr_setschedparam calls Bug#37536: Thread scheduling causes performance degradation at low thread count Deprecated --skip-thread-priority startup option as newer versions of the server won't change the thread priorities by default. Giving threads different priorities might yield marginal improvements in some platforms (where it actually works) but on the other hand it might cause significant degradation depending on the thread count and number of processors. Meddling with the thread priorities is a not a safe bet as it is very dependent on the behavior of the cpu scheduler and system where MySQL is being run. From MySQL 6.0 and up the default behavior is that of not modifying the threads priorities. modified: sql/mysqld.cc 2692 Davi Arnaut 2008-09-30 Bug#34306: Can't make copy of log tables when server binary log is enabled Post-merge bug fix: lock_type is a enumeration type and not a bit mask. modified: sql/sql_cache.cc === modified file 'sql/mysqld.cc' --- a/sql/mysqld.cc 2008-09-29 13:53:40 +0000 +++ b/sql/mysqld.cc 2008-10-01 12:24:35 +0000 @@ -6223,7 +6223,7 @@ Can't be set to 1 if --log-slave-updates {"skip-symlink", OPT_SKIP_SYMLINKS, "Don't allow symlinking of tables. Deprecated option. Use --skip-symbolic-links instead.", 0, 0, 0, GET_NO_ARG, NO_ARG, 0, 0, 0, 0, 0, 0}, {"skip-thread-priority", OPT_SKIP_PRIOR, - "Don't give threads different priorities.", 0, 0, 0, GET_NO_ARG, NO_ARG, + "Don't give threads different priorities. Deprecated option.", 0, 0, 0, GET_NO_ARG, NO_ARG, DEFAULT_SKIP_THREAD_PRIORITY, 0, 0, 0, 0, 0}, #ifdef HAVE_REPLICATION {"slave-load-tmpdir", OPT_SLAVE_LOAD_TMPDIR, @@ -7865,6 +7865,9 @@ mysqld_get_one_option(int optid, break; case (int) OPT_SKIP_PRIOR: opt_specialflag|= SPECIAL_NO_PRIOR; + sql_print_warning("The --skip-thread-priority startup option is deprecated " + "and will be removed in MySQL 7.0. MySQL 6.0 and up do not " + "give threads different priorities."); break; case (int) OPT_SKIP_LOCK: opt_external_locking=0;