One of the very frequent cases with performance problems with MySQL is what they happen every so often or certain times. … need to know it is not MySQL problem, might be even not problem with your MySQL configuration, queries and hardware, even though fixing… too much in this case throttling by having relatively short queries and introducing “sleeps” between them can be a good idea…
Post: Introducing the pmp-check-mysql-status Nagios Plugin
March 29, 2012 By Leave a Comment
Most of the Nagios plugins included with the Percona Monitoring …I found in my research to be frequent, severe, or subtle causes of problems in MySQL systems. They are intentionally not …change over time for one or more counters (e.g. queries per second) The documentation contains examples of how to …
Post: Reasons for MySQL Replication Lag
July 29, 2011 By 6 Comments
…size could cause performance problems. MySQL Restart MySQL Restarts may include recovery time but what is the most important they often come with…could be even system which queries mysql. I’ve seen monitoring updates which would add excessively expensive and frequent query on information_schema which…
Post: Is it query which needs to be optimized ?
March 6, 2007 By 9 Comments
… at MySQL Performance Forum as well as from our customers regarding query optimization… which had one thing in common – It is not query… Schema Design standpoint it is best to make sure your most frequent queries do not need GROUP BY. It can be reachable by… frequently I see dynamic query generation when some query variants fall back to use filesort, and it does not take many of such queries…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
… the top 10 most expensive queries, in total execution time. By the way, the slow query logs in the stock MySQL server are extremely… in the slow query log output. The stock MySQL server’s limitation of one-second granularity makes it hide problem queries that are… proxies, and high availability solutions, all of which we can frequently help customers set up much more efficiently and with better…
Post: MySQL caching methods and tips
April 4, 2011 By 4 Comments
… of the most common cache methods for MySQL. Popular cache methods The MySQL query cache When the query cache is enabled, MySQL examines each query to see… keys which are not accessed very frequently. Use what you need Both Memcached and the MySQL query cache are limited in size. If…
Post: Managing Slave Lag with MySQL Replication
October 12, 2007 By 11 Comments
… application and from load to load. Plus what is the most important within same application the lag will likely have spikes… spikes as load spikes will frequently cause replication lag spikes as well. Locks – MySQL Replication SQL Thread executes queries same as any other… TABLE, though running it on Master is frequently not an option either. So this query is often run directly on the Slave…
Post: The story of one MySQL Upgrade
October 8, 2010 By 8 Comments
… mysql_fix_privilege_tables to ensure all new privileges are added, which is something I frequently see forgotten Next step is setup MySQL… remove them and we were down to only query time differences. In most cases query time differences were not significant or Percona Server… if it includes skilled MySQL DBA typically does not need to go through major version upgrades more frequently than 3-5 years…
Post: MySQL Slow query log in the table
May 31, 2007 By Leave a Comment
As of MySQL 5.1 get MySQL slow query log logged in mysql.slow_log table instead of the file as you had …” query by removing comments and replacing constants with some placeholders as this would allow to aggregate log entirely in SQL finding most frequent slow query types or queries which load server the most. The other handly feature would be…
Post: How to Monitor MySQL with Percona's Nagios Plugins
February 22, 2012 By 8 Comments
…and lock wait timeouts, covered in another plugin) are frequent causes of serious errors in applications because …server is alive and responds to a query. The pmp-check-mysql-status is also very flexible and… the current plugins already cover some of the most common and severe conditions that we’ve …
