… MySQL manual, especially the option and…Slow_launch_threadsblogpercona.commanual slow_launch_timeblogpercona.commanual Slow_queriesblogpercona.commanual slow_query_logblogpercona.commanual slow_query_log…unique_checksblogpercona.commanual updatable_views_with_limitblogpercona.commanual …
Post: Logging MySQL queries from the client instead of the server
February 2, 2011 By 2 Comments
The “slow query log” is the single most valuable way to examine query execution on your MySQL server. Queries are logged with timing information, and in the… be able to see both views of query execution time. Why would you want to see the query timing information from the application…
Post: Computing 95 percentile in MySQL
November 28, 2008 By 5 Comments
…”. Lets set you have 10000 page views or queries and have average response time of…slow search page. So you have defined your response time in terms of 95/99 percentile and get your logs…by running following order-by queries: mysql> select wtime from performance_log_081128 where page_type=’search…
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… great for the glance view. mysqlsla This is nice tool to analyze slow query log. It reads bunch of different log formats and has various stats, and it was there before pt-query-digest appeared…
Comment: Win a free ticket to RailsConf!
May 15, 2011 By 10 Comments
… should never roll your log file. See my views at http://ronaldbradford.com/blog/the-correct-approach-to-rolling-mysql-logs-2010-02-22… about issues with how to roll the slow query log, and about changes in log file writing in MySQL 5.5 that affects historical processes.
Post: What's required to tune MySQL?
July 27, 2011 By 4 Comments
…should expect to deliver huge wins. If MySQL is actually badly configured, you can … the InnoDB buffer pool size or log file size, and not using InnoDB. … happens when you have query cache contention, DNS problems, or very slow I/O. In … it’s important to have an overall view of the server to form a …
Post: On Good Instrumentation
May 31, 2010 By 1 Comment
… look at the system from bird eye view – system needs to process transactions and you…queries or their performance. If I see 2 queries taking 30 seconds it is clearly slow queries. If it is 10.000 queries…in MySQL Query Log. What is important is however to be able to connect the data from these logs -…
Post: ACTIVE with Locks – Now thats a problem !
June 2, 2011 By 2 Comments
…like in this case: MySQL thread id 2059, query id 1014425 10.10.10.10 user Trx read view will not see… 368, 1 row lock(s), undo log entries 1 MySQL thread id 1720, query id 1011283 10.10.10.10 user … old transaction and so you can get system to slow down because of maintaining many old row versions. I…
Post: Just do the math!
July 6, 2009 By 4 Comments
… doing some reports from your apache log files – how many distinct visitors hit… 10000 page views a day you few days of history the queries there instant…. There are couple of ways MySQL may execute query above but lest focus on… of index accesses, joins etc may be slowed down 100-1000 then going from…
Post: Percona Testing: Innodb crash / recovery tests available
December 21, 2011 By Leave a Comment
…, but we use the random query generator for generating our… seemed very, very slow I just like the …_IF(“crash_commit_after_log“, DBUG_SUICIDE();); DBUG_EXECUTE…view the comparisons of master-slave checksums after the master has crashed and restarted: $ ./kewpie.py –suite=innodbCrash –basedir=mysql…
