… top mutexes is &buf_pool->mutex,&new_index->lock. I profiled 5.6.11 in this IO bound scenario with the perf – see profile below: # Overhead Samples Command Shared Object # …….. ………. ……. ………………. …………………………………………………………………………………………………………………. # 35.85% 17738833…
Post: Webinar: SQL Query Patterns, Optimized
May 20, 2013 By Leave a Comment
… optimal query efficiency. The discussion will cover optimizer reports, query profiling, and session status to measure performance. The query patterns will…
Post: High-load problems? Investigate them with 'pt-query-digest'
April 23, 2013 By 2 Comments
… ran that by pt-query-digest –type rawlog –report-format profile, to get just the ranking of queries. To my luck…
Post: How to convert MySQL's SHOW PROFILES into a real profile
February 20, 2012 By 12 Comments
…” included with the Sakila sample database to demonstrate: mysql> SET profiling=1; mysql> pager cat > /dev/null mysql> SELECT * FROM nicer… 0.18 seconds. Where did the time go? mysql> SHOW PROFILE FOR QUERY 1; +———————-+———-+ | Status | Duration | +———————-+———-+ | starting | 0.000032 | | checking permissions…
Post: Profiling MySQL stored routines
January 19, 2009 By 4 Comments
… queries are being executed. This is where Jeremy’s SHOW PROFILE patch – which is included in all Community tree based Percona… time they spent executing but we can also get a profile for each of the queries individually. I think this is… digging deeper. On the other hand, this way of manual profiling you can’t really see real time stats, for example…
Post: Profiling MySQL Memory Usage With Valgrind Massif
January 9, 2013 By 3 Comments
… memory overall. Or again, maybe you noticed mysqld’s memory profile slowly growing overtime, indicating a possible memory bug. Whatever the reason, there is a simple but powerful way to profile MySQL memory usage; the Massif tool from Valgrind. An excerpt… get a debug build of mysqld to use for memory profiling purposes: Download the appropriate debuginfo packages (these may not be…
Post: Three ways that the poor man's profiler can hurt MySQL
December 2, 2011 By 19 Comments
… few years, Domas’s technique of using GDB as a profiler has become a key tool in helping us analyze MySQL…
Post: MySQL: Followup on UNION for query optimization, Query profiling
August 14, 2006 By 14 Comments
… couple of rows. Let me however show how you can profile queries to see what exactly happens during query execution – very…
Post: 5.0.77 / 5.0.82 -build16 Percona binaries
June 11, 2009 By 4 Comments
… SHOW PROFILE to query information in slow.log output. profiling_server. This variable ( ON / OFF ) enables profiling of all queries (in all connections). profiling… usage of getrusage function in profiling. Be careful, enabling profiling_server may cause performance degradation, especially with profiling_use_getrusage. innodb_extra_rseg…
Post: Percona XtraDB Cluster: SElinux is not always the culprit !
December 20, 2012 By 5 Comments
… culprit is called : AppArmor ! Percona doesn’t provide any AppArmor profile for PXC, but it seems that on this server (Ubuntu… : root@testmachine:~# apparmor_status apparmor module is loaded. 7 profiles are loaded. 7 profiles are in enforce mode. /sbin/dhclient /usr/lib…/sbin/ntpd /usr/sbin/tcpdump 0 profiles are in complain mode. 2 processes have profiles defined. 2 processes are in enforce mode…
