…used option which as per manual will chose best value automatically. Making this change I could bring optimization, and full query execution time to…to no more than 7 at which complexity is reasonable. This makes Timour explanation somewhat conflicting though as if we assume MySQL…
Post: Should we give a MySQL Query Cache a second chance ?
April 10, 2011 By 63 Comments
…to Query Cache to make it cool again. The question is whenever anyone from “MySQL Market Players” – Oracle, MariaDB, Drizzle, Percona Server, will allocate resources to…
Post: Performance impact of complex queries
January 17, 2007 By 11 Comments
…MySQL Performance by complex queries on large data sets(ie some large aggregate queries) and batch jobs. It is not rare to see queries…Make sure the load is low enough so your complex query or batch job do not slow things to…
Post: Using any general purpose computer as a special purpose SIMD computer
May 16, 2011 By 6 Comments
…use this technology constructively and for peaceful purposes. Love one another and let’s solve all the complex…operation burns one CPU. To help completely demonstrate how Shard-Query makes parallel set operations work…MySQL client. This will be a linear operation because Shard-Query has no idea how to…
Post: High-Performance Click Analysis with MySQL
December 22, 2008 By 13 Comments
… columns to support these queries. But beware of denormalizing with character data; try to make your…still have to think about how to avoid enormous tables that are hard to maintain, back…complex query with many joins. I have never seen this approach scale well. Use The Best Technologies You Can MySQL…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…query.) If it’s not possible to use a patched binary, we can use MySQL Proxy, packet sniffing, or other techniques to…how to interpret what we’re showing, and why the proposed modifications are better. If the client approves it, we may make…
Post: 10+ Ways to Crash or Overload MySQL
November 13, 2007 By 20 Comments
… make server unavailable plus in many cases you can use result overload to make MySQL to…users being unable to run their queries. Stored Procedures – How much memory can …queries to get MySQL Server barely functional. The limits which exist are not really helpful as they do not define query complexity…
Post: MySQL Server Memory Usage
May 17, 2006 By 18 Comments
…how should they estimate memory consumption by MySQL Server in given configuration. What is the formula they could use. The reasons to…be crashing , failing to execute queries or make operation to swap seriously slowing down… not need to increase per thread buffers unless you have complex queries. …
Post: MySQL EXPLAIN limits and errors.
July 24, 2006 By 6 Comments
…, especially now as MySQL has triggers which can make updates very different. Also there is no way to tell you how ALTER table would… examine your queries manually but if you have automatic tool which catches possibly complex queries it can give you head ache. filesort, using temporary are always in the first line So it is impossible to tell…
Post: Why MySQL could be slow with large tables ?
June 9, 2006 By 139 Comments
…solution is to make sure …how large proportion of rows matches to…used to compose the complex object which was previously normalized to several tables or perform complex queries…MySQL single query runs as single thread (with exeption of MySQL Cluster) and MySQL issues IO requests one by one for query…
