…as SHOW TABLE_STATISTICS, SHOW INDEX_STATISTICS and SHOW USER_STATISTICS. The first two can interest anyone to periodically check what data or which index …statistics on the database activity broken down by users, tables or indexes. Monitoring those numbers every minute can show you changes in usage…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…SHOW INNODB STATUS is command which prints out a lot of internal Innodb performance counters, statistics…index. You can also see number of hash index lookups and number of non-hash index lookups which is indication of hash index…1000 This section shows Buffer pool activity and memory usage. You can …
Post: Percona builds with Percona patchsets
July 16, 2008 By 35 Comments
… in slow logs) execution plan (show info about query execution in slow log) InnoDB statistic (show extended InnoDB usage during query execution in slow log) Google’s patches with user statistics, and statistics about tables and indexes usage You can…
Post: Introducing percona-patches for 5.1
February 9, 2010 By 21 Comments
… improvements to the slow log output, and INDEX_STATISTICS). Despite having many requests to port …Different patches to help with day to day usage of MySQL ® Two new features … can get additional THREADS_STATISTICS which show similar information to USER/CLIENT_STATISTICS but per THREAD granularity…
Post: Percona Server and XtraBackup weekly news, February 5th
February 6, 2011 By 2 Comments
… name changes to command-line options and SHOW VARIABLES variables. And Fred Linhoss committed some… on a bug that makes the INDEX_STATISTICS and TABLE_STATISTICS tables under-report by 1 the… XtraBackup news: In general, demand for and usage of XtraBackup continues to grow extremely quickly,…
Comment: Duplicate indexes and redundant indexes
January 19, 2012 By 38 Comments
… dept(deptid) ); * Find below output which shows indexes in the database. (Query for …INNER JOIN information_schema.key_column_usage b ON a.constraint_name = …index separator ‘, ‘), char) as column_list, null as referenced_table_name, null as referenced_column_name FROM information_schema.statistics…
Post: The new cool MySQL patch has landed! Check your queries performance!
October 31, 2007 By 16 Comments
…. Full_join means any of the joins didn’t use indexes. If a temporary table is required for query execution Tmp…. INNODB USAGE The final part are the InnoDB usage statistics. MySQL currently allows you to see many per-session statistics for operations with SHOW SESSION… # Filesort: No Disk_filesort: No Merge_passes: 0 # No InnoDB statistics available for this query SELECT COUNT(1) FROM t2; Important…
Post: ORDER BY ... LIMIT Performance Optimization
September 1, 2006 By 100 Comments
…or by examining Hander statistics). If only 50 …expressions or functions will block index usage for order by. Sort…index | NULL | k | 772 | NULL | 1638400 | | +—-+————-+——-+——-+—————+——+———+——+———+——-+ 1 row in set (0.03 sec) See – “rows” is showing…
Post: MySQL on Amazon RDS part 1: insert performance
March 15, 2011 By 37 Comments
…dedicated to RDS, not shared with the general usage of AWS as you get on normal … 400,000,000 rows. This creates a table+index data size approximately twice as big as memory,…statistics and finer-grained samples, say, every 5 seconds instead of every minute, and some samples of more data such as SHOW…
