…here and from the Percona Software Repositories). Based on MySQL 5.5.22, including all the bug fixes … All of Percona‘s software is open-source and free, all the details of the release can be … Bugs Fixed: While running the test case found that MEMORY engine may return rows in non-deterministic order …
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
…memory is being used by current MEMORY tables: mysql> select sum(data_length+index_length) from information_schema.tables where engine=’memory‘; …406936 + 18144) Dictionary memory allocated 2623331 Buffer pool size 7864319 Buffer pool size, bytes 128849002496 Free buffers 1 Database…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
… in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a… optimizer enhancement Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5.5 Now let’s take…
Post: Percona Server 5.5.21-25.1 released!
March 29, 2012 By 8 Comments
…All of Percona‘s software is open-source and free, all the details of the release can be …we wish to make available. Bugs Fixed: Fixed a memory corruption regression introduced in 5.5.18-23.0… CentOS 5. Bug fixed #962940 (Laurynas Biveinis). Fixed MySQL upstream bug #64160 that was causing issues on …
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
… the amazing MySQL manual, especially the option and variable …_thread_idblogpercona.commanual Qcache_free_blocksblogpercona.commanual Qcache_free_memoryblogpercona.commanual Qcache_…idblogpercona.commanual shared_memoryblogpercona.commanual shared_memory_base_nameblogpercona.commanual show_slave_…
Post: How to Monitor MySQL with Percona's Nagios Plugins
February 22, 2012 By 8 Comments
… down for a system reboot. The pmp-check-mysql-pidfile plugin verifies that MySQL‘s PID file exists. Evidence of contention in… is allocating too much memory. A runaway server process, or poorly optimized queries, can consume too much memory and cause the server… pmp-check-unix-memory plugin checks for a single process consuming too much memory and/or for too little free memory in general. This…
Post: InnoDB memory allocation, ulimit, and OpenSUSE
August 23, 2010 By 7 Comments
… the extra 3.37 GB allocation, there was still some free memory. Or was there? Maybe some hidden monster was eating it…. Apparenly OpenSUSE defaults are set in proportion to physical memory to keep the memory-hungry applications from taking the system down. On… physical memory, 2 GB swap it decided to set the virtual memory ulimit (-v) to 77.27 GB, and the physical memory (-m…
Post: MySQL Query Cache
July 27, 2006 By 69 Comments
… great feature called “Query Cache” which is quite helpful for MySQL Performance optimization tasks but there are number of things you… can be seen as large value of Qcache_free_blocks relatively to Qcache_free_memory. FLUSH QUERY CACHE command can be used for… and watch Qcache_free_memory and Qcache_lowmem_prunes – If you’re not getting much of lowmem_prunes and free_memory stays high you…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
…: mtr_commit (sync0sync.ic:221) ==9090== by 0x6B39223: fsp_fill_free_list (fsp0fsp.c:1455) ==9090== by 0x6B3DED8: fsp_header_init… the waiters field next, the read must be serialized in memory after the reset. A speculative processor might perform the read…, I’d consider backporting and using MySQL 5.5 atomic operation primitives with proper memory barriers, so that there is no need…
Post: Memory allocation in Stored Function
August 26, 2007 By 8 Comments
… with no free memory and giant swap. The case was worth to look deeply – let’s try simple table (experiments with MySQL 5… check only select: mysql> select avg(length(hello(name))) from testf; and here is vmstat 5 output: procs ———–memory———- —swap– —–io—- –system… As you see MySQL ate 5GB of memory in 85 sec. That makes things clearer. As I understand MySQL allocates memory in each call…
