… is necessary when running a large stream of queries. Benchmarks We benchmarked with slow query logs captured from our production systems. We restored… database was consistent before applying the captured query traffic. This is an important step because update statements that match no rows or…
Post: MySQL 5.6 Compatible Percona Toolkit 2.2 Released
March 25, 2013 By 2 Comments
…-new pt-upgrade was written once long ago and not updated since. Now that we have four base versions of MySQL… now (slow, general, binary, and tcpdump), so you shouldn’t have a problem finding queries to run and compare. pt-query-digest is simpler pt-query-digest 2.2 has fewer…
Post: MySQL Slow query log in the table
May 31, 2007 By 1 Comment
As of MySQL 5.1 get MySQL slow query log logged in mysql.slow_log table instead of the file as you had… as you require. Doing so however may affect your performance – updating table with a lot of indexes may be significant overhead… to aggregate log entirely in SQL finding most frequent slow query types or queries which load server the most. The other handly feature…
Post: Slow Query Log analyzes tools
September 6, 2006 By 84 Comments
… Slow Query Log – Especially after the changes to log all queries slow query log may be growing too rapidly to follow, so we implemented slow query log… may help to one queries but hurt others, for example adding indexes often help SELECT queries but slow down INSERT/UPDATE ones. Final Note… standard slow query log format as well. Update 2009-03-04: most of us at Percona now use mk-query-digest from Maatkit for slow query…
Post: Updated msl (microslow) patch, installation walk-through!
April 20, 2008 By 17 Comments
For a couple of months there have been no updates to our msl patch, however recently I managed some time …_query_time AND min_examined_row_limit AND log_slow_filter. log-slow-queries[=name] Log slow queries to this log file. Defaults logging to hostname-slow.log file. Must be enabled to activate other slow…
Post: Managing Slave Lag with MySQL Replication
October 12, 2007 By 15 Comments
… you normally start with query chopping making sure all your update queries are short. If you need to update 1.000.000 rows you do not do it in the same query but… MySQL Slow Query Log does not log replication queries. Though this is one of few slow query logging improvements you can get with our Slow Query Log…
Post: Figuring out what limits MySQL Replication
March 7, 2007 By Leave a Comment
… on slow query log, happily the server was running MySQL with slow query log with microsecond resolution so I could check exactly which update queries take most time to execute. Unfortunately it did not work because Slave thread seems to have problems picking up long_query…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
… have enabled slow query logging and set a low enough value for long_query_time. We normally use a value of long_query_time… pt-query-digest Using pt-query-digest is pretty straight forward: pt-query-digest /path/to/slow-query.log Note that executing pt-query-digest can….1956 2.4% 89 0.0022 1.00 0.01 UPDATE wp_options # 7 0x7AEDF19FDD3A33F1 0.1381 1.7% 909 0…
Post: Fighting MySQL Replication Lag
September 22, 2008 By 7 Comments
… 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… update queries. In such case slave will only need to run UPDATE Example: UPDATE posts SET spam=1 WHERE body LIKE “%cheap rolex%”; This query… in many cases is to simply space it out and slow down your batch job (such as adding sleep calls) to…
Post: The new cool MySQL patch has landed! Check your queries performance!
October 31, 2007 By 16 Comments
… an updated version of the patch. The basic idea is the same as for its predecessor – to get more information about query… behavior with the new parameter –log-slow-slave-statements. THE DETAILED INFORMATION ABOUT QUERY EXECUTION Each query can be executed in various ways… full slow log entry for a query using InnoDB can look like this: # User@Host: macko[macko] @ localhost [] # Thread_id: 4 # Query_time…
