… just introduced you to the query performance magic bullet, unfortunately, I haven’t. The problem with the query cache is “coarse invalidation”. That… cache stampedes are essentially the cause of the unpredictable performance of the MySQL query cache, since the rate of invalidation can not be…
Post: Why MySQL could be slow with large tables ?
June 9, 2006 By 139 Comments
…previously normalized to several tables or perform complex queries finding relationships between objects. …MySQL single query runs as single thread (with exeption of MySQL Cluster) and MySQL issues IO requests one by one for query…large data sets and complex queries here are few tips Try to fit …
Post: ORDER BY ... LIMIT Performance Optimization
September 1, 2006 By 93 Comments
… together with LIMIT is often the cause of MySQL Performance problems. Here is what you need to know…simple MySQL using multiple indexes on most selective columns would be good idea for performance of such queries. For…just 5 in this case. Many of the tips I’ve mentioned here work for ORDER BY…
Post: Is your server's performance about to degrade?
May 18, 2010 By 13 Comments
…tipping point in the data size, or something like that. It suddenly caused the query cache to become an enormous bottleneck. The query…I was able to see queries that have mostly very fast performance, and occasionally have much…and that’s where improvements to the MySQL source code are necessary. But …
Post: How to Monitor MySQL with Percona's Nagios Plugins
February 22, 2012 By 8 Comments
…mysql-innodb plugin checks for several indicators of severe internal problems within InnoDB, such as contention that crosses a tipping… there are several others that can be performed with existing plugins, so there was …is alive and responds to a query. The pmp-check-mysql-status is also very flexible…
Comment: Using delayed JOIN to optimize count(*) and LIMIT queries
April 25, 2007 By 22 Comments
[...] MySQL Performance Blog » Using delayed JOIN to optimize count(*) and LIMIT queries (tags: Tech Database MySQL Performance Tips) [...]
Page: Presentations
May 3, 2006 By
…covers some basic rules of queries optimization for MySQL including application based tuning such as avoiding queries if you do …MySQL performance giving some advice of selecting prover values for them. Download MySQL Performance CookBook MySQL Users Conference 2007, Santa Clara,CA, April 2007 Tips…
Post: SELECT UNION Results INTO OUTFILE
September 14, 2011 By Leave a Comment
…a quick tip I know some of us has overlooked at some… OUFILE from this. Using the employees.employees table: mysql [localhost] {msandbox} (employees) > EXPLAIN SELECT * INTO OUTFILE ‘/home… queries, making the latter more performant than the former. Of course you can stil break all this UNION queries …
Post: MySQL Replication vs DRBD Battles
April 28, 2008 By 12 Comments
…or further degraded performance. In the large databases I run in production relaying on MySQL Replication for …data at the same time as running reporting queries on last month. All last month will … ensured consistency – MySQL Replication can out of sync – and there is bunch of tips in documentation …
Post: MySQL Error Message Nonsenses
March 16, 2008 By 7 Comments
…much better if MySQL would give error give exact position of error (with complex auto generated queries line number … public road map either. Though this is just tip of the iceberg of not so helpful or … to tell you why operation could not be performed (read error, out of file descriptors etc). In …
