…tc_sizeblogpercona.commanual log_warningsblogpercona.commanual long_query_timeblogpercona.commanual low_priority_updatesblogpercona….commanual Threads_runningblogpercona.commanual time_formatblogpercona.commanual time_zoneblogpercona.commanual timed_mutexesblogpercona.commanual timestampblogpercona….
Post: 5.0.75-build12 Percona binaries
January 23, 2009 By 18 Comments
… variable use_global_long_query_time, which allows all current threads see change of long_query_time. By default value set in SET GLOBAL long_query_time=N command… on Rails application. With use_global_long_query_time=true even all current threads will respect SET GLOBAL long_query_time=N. The feature made for…
Post: Fighting MySQL Replication Lag
September 22, 2008 By 7 Comments
… have any long running updates. Queries or transactions containing multiple update queries which add up to long time. I would keep the maximum query length at… extremely complicated query. It is best to avoid INSERT … SELECT going through replication in 5.0 for many reasons (locking, long query time, waste…
Comment: Backport of micro-time patch to mysql 4.1
October 9, 2006 By 9 Comments
I patch mysql source, but it doesn’t work. I can not set long_query_time=0 . The least value of long_query_time – 1. If I set long_query_time=0, “SHOW VARIABLES;” show me long_query_time=1. And I see always seconds in slow log: Query_time: 2 Lock_time: 0 . How to turn on the patch?
Post: Replaying database load with Percona Playback
October 25, 2012 By 9 Comments
… the peak time to get valuable information: SET GLOBAL slow_query_log=1; SET GLOBAL long_query_time=0; With long_query_time we are logging all queries that are being executed in our database. After capturing enough data and copying the slow query log…
Post: How to use tcpdump on very busy hosts
April 18, 2011 By 17 Comments
…: use “mk-query-digest –filter ‘$event->{time} && $event->{time} > 1′” to exclude all queries which it believes took longer than the servers long-query-time of 1… has an obvious flaw — if your long-query-time is 1 second, and mkqd believes that a query which actually took 10ms instead took…
Post: Figuring out what limits MySQL Replication
March 7, 2007 By Leave a Comment
… update queries take most time to execute. Unfortunately it did not work because Slave thread seems to have problems picking up long_query_time when it is set online, meaning changing it via set global long_query_time=0 and restarting slave…
Post: Common MySQL traps webinar questions followup
January 17, 2013 By 1 Comment
… full slow query logging (with long_query_time = 0) for some time during peak load. Then you can use pt-query-digest to analyze the queries and have a report of the queries that… single query takes most of the total response time of the server: that’s typical of a hot spot and this query is…
Post: DROP TABLE and stalls: Lazy Drop Table in Percona Server and the new fixes in MySQL
June 22, 2012 By 33 Comments
… its a shared lock, so while read queries can still access AHI, write queries would have to wait till the latch is… table creation time does not skew the results of the benchmark. During the entire run of the benchmark, all the queries were captured in the slow log by setting long_query_time to 0. Then for analysis purposes the queries in the slow…
Post: Percona Server 5.1.53-12.4
December 29, 2010 By Leave a Comment
…_slow_timestamp_every, log_slow_sp_statements, slow_query_log_microseconds_timestamp, use_global_long_query_time. (Oleg Tsarev) Bug #673567 – Compiler could produce… tests of options log_slow_slave_statements and use_global_long_query_time work only on statement-based replication. They were failing when…
