…is quite helpful for MySQL Performance optimization …SHOW commands or stored procedure calls are not, even if stored procedure would simply preform select to retrieve data from table…table modifications – if there are a lot of queries being cached this might reduce update speed a bit. Fragmentation…
Post: Write contentions on the query cache
September 5, 2012 By 5 Comments
…MySQL executes this query. So I used commands you’re probably familiar with: EXPLAIN, SHOW PROFILE, SHOW…0.000004 | | checking permissions | 0.000004 | | Opening tables | 0.000021 | | System lock | 0.000009 | | init… this could increase the fragmentation of the cache and …
Post: Percona build7 with latest patches
November 14, 2008 By 26 Comments
We made new binaries for MySQL 5.0.67 build 7 which include patches we recently … to check fragmentation of the last InnoDB scan | 1.0 | Percona | GPL | The names are Innodb_scan_* | | userstatsv2.patch | SHOW USER/TABLE/INDEX statistics | V2 | Google | GPL | Added INFORMATION_SCHEMA.*_STATISTICS | | show_patches.patch | SHOW PATCHES | 1.0 | Jeremy…
Post: Read Buffers, mmap, malloc and MySQL Performance
September 12, 2007 By 8 Comments
… together with strace) are great tools for MySQL Performance analyses. Too many people … much slower than Monty results show. Mmap allocation process can be split … get expensive if virtual memory gets fragmented. A while ago I measured …if you have small table or LIMIT 10 in full table scan query you …
Post: MySQL 5.6: Improvements in the Nutshell
January 27, 2013 By 16 Comments
…available in MySQL 5….Fragmentation – Reduced Locking for Partitioned tables – Reduced Contention for LOCK_open – Support for multiple table…Table Access instrumentation – - Statements instrumentation – - Stages Instrumentation – - Aggregations by User, Host etc – - Network IO Instrumentation – - Show…
Post: Improved InnoDB fast index creation
November 6, 2011 By 4 Comments
…mysql> SHOW PROFILE; +——————————+————+ | Status | Duration | +——————————+————+ . . . | copy to tmp table | 184.694432 | . . . +——————————+————+ 18 rows in set (0.00 sec) mysql…
Page: Tools
May 30, 2008 By 31 Comments
… Toolkit Percona Toolkit is a great set of tools for MySQL Performance Analyses and maintainence. Must know and have for any… filefrag is the fool to check fragmentation of the file. Ever wondered how fragmented your tablespace or table on the file level ? iostat iostat tool is a great help investigating/troubleshooting IO problems – it will show…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
…of a segment are allocated from ‘fragment extents’ where any individual page …_innodb.cc in 5.1: static MYSQL_SYSVAR_ULONG(thread_concurrency, srv_thread…lots of threads waiting for semaphores in SHOW INNODB STATUS), you can try … ORDER and ORDERLINE tables are joined to form a single table), it might …
Post: Falcon Storage Engine Design Review
January 12, 2007 By 19 Comments
…it will give. As “SHOW TABLE STATUS” is not showing index sized in the …been implemented outside of MySQL Storage Engine level for MySQL – reading rows in their…show themselves in practice. The other interesting point which I have not found much information about is regarding handling fragmentation…
Post: Moving from MyISAM to Innodb or XtraDB. Basics
November 22, 2010 By 2 Comments
…. Space Innodb Tables tend to be larger. Again converting schema will show you some … and usage Innodb tables may increase in size significantly due to fragmentation. Usage Differences…table/index scan for Innodb. Defaults You need to know two things about defaults for Innodb. First Depending on MySQL…
