… with a fast PCI-e flash card as storage. By default linkbench dataset has 10M ids(after …drop in MySQL 5.6. In IO-bound cases MySQL still has performance issues around mutexes and Percona Server shows …-cache=1000 query_cache_size=0 query_cache_type=0 performance_schema=0 #56only loose-innodb_flush_…
Post: Virident vCache vs. FlashCache: Part 2
May 17, 2013 By 3 Comments
…MySQL as if it were using SSD storage or to just use an optimized HDD storage… line – SSD config) which shows the most consistent performance. …type=pareto \ –forced-shutdown=1 –max-time=7200 –max-requests=0 –percentile=95 \ –mysql-user=root –mysql-socket=/tmp/mysql.sock –mysql…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
…MySQL manual,…show_statusblogpercona.commanual Com_show_storage_enginesblogpercona.commanual Com_show_table_statusblogpercona.commanual Com_show_tablesblogpercona.commanual Com_show_triggersblogpercona.commanual Com_show_variablesblogpercona.commanual Com_show… slave_type_conversionsblogpercona….
Post: MySQL opening .frm even when table is in table definition cache
November 21, 2011 By 8 Comments
… view of how the Storage Engine API is called. But back to what the above strace shows. In MySQL 5.5 you can find in sql/datadict.cc a function named dd_frm_type(). In MySQL 5.1… the DB_TYPE. i.e. what storage engine it is. We can ignore the upper limit on number of storage engines for MySQL and…
Post: How to Monitor MySQL with Percona's Nagios Plugins
February 22, 2012 By 11 Comments
…mysql-pidfile plugin verifies that MySQL‘s PID file exists. Evidence of contention in the processlist. The pmp-check-mysql-processlist plugin checks SHOW… the server as well as the storage engine. For example, a pile-up … include more plugins to monitor more types of problems, but the current plugins …
Post: Troubleshooting MySQL Upgrade Performance Regressions
February 15, 2012 By Leave a Comment
…old and new MySQL Server version and observing the difference. Sometimes though it might not show performance …times or even workload consisting of several query types. Though it is rather rare for this …stats-method and myisam-stats-method. For Innodb storage engines it is possible for stats to …
Post: Testing MySQL column stores
August 16, 2010 By 15 Comments
… an objective viewpoint. I performed two different types of testing. The first focused on core… have experience developing such cases for MySQL column-based storage engines in the past. I reported… significant defects in Infobright that would be “show stoppers” for typical OLAP analysis queries. These…
Post: MySQL Error Message Nonsenses
March 16, 2008 By 7 Comments
…sl1 ~]$ perror 124 OS error code 124: Wrong medium type MySQL error code 124: Wrong index given to …running concurrently? I hope with pluggable storage engine interface Sun/MySQL spends some time to make things consistent… related but you also need to run SHOW INNODB STATUS to see what exactly Innodb …
Post: Efficient Boolean value storage for Innodb Tables
April 23, 2008 By 6 Comments
… flag storage in Innodb (not accounting for standard row overhead) if we use BIT(1), TINYINT or ENUM types but …`c10` char(0) default NULL ) ENGINE=InnoDB DEFAULT CHARSET=latin1 mysql> show table status like “%bool%” \G *************************** 1. row *************************** Name: bbool …
Post: The MySQL optimizer, the OS cache, and sequential versus random I/O
April 28, 2008 By 17 Comments
…storage engine; the optimizer doesn’t know how a given storage…length: 11993816064 mysql> show table status like ‘……. +——-+———–+———–+———————————+ | table | type | rows | Extra | +——-+———–+———–+———————————+ | fact | ALL |…
