…other ways to get this information, too. The last three commands are for giving me information …costs and benefits on the system as a whole. The queries the system runs, and hence the slow query…most expensive queries, in total execution time. By the way, the slow query logs in the stock MySQL server…
Post: Percona's Commitments to MySQL Users
November 5, 2010 By 10 Comments
…MySQL development suffered some detours and slowdowns over the last few years. This era is over. MySQL…, query analysis, replication management, and other capabilities. If you’re worried about Oracle making MySQL… unlimited servers and CPUs, because the cost of providing support is not related …
Post: MySQL Replication vs DRBD Battles
April 28, 2008 By 12 Comments
… running reporting queries on last month. All last month will be hot on the slave which is doing reads but only last few hours… paying extra performance costs. It is worth to note DRBD also allows building very nice mixed environments with MySQL – for example you… transaction loss and automated fail over. Whenever you’re using MySQL Cluster, DRBD or MySQL Replication you have to have some compromises.
Post: MySQL Backup tools used by Percona Remote DBA for MySQL
March 13, 2013 By 8 Comments
… Tips/Tricks: run with –kill-long-queries to avoid nasty problems with “… all slaves mysqlbinlog 5.6 Last year Percona IT director Tamas …convenient feature and allows you to cost effectively store long term backups … term backups Decompressing Percona XtraBackup for MySQL in parallel using all your …
Post: MySQL caching methods and tips
April 4, 2011 By 5 Comments
…the cloud, results in decreased overall operational costs, so caches provide real value by… MySQL. Popular cache methods The MySQL query cache When the query cache is enabled, MySQL examines each query … information that changed since they were last populated. MySQL includes two statements that make …
Post: PHP Large result sets and summary tables.
July 6, 2007 By 8 Comments
…cost of creating temporary table though which can be quite high. Sharing connection no more works If you use buffered query…buffered query the only real call you can get errors is when you run mysql_query , mysql_…ranges instead. I would especially recommend this last way for very long processes, ie …
Post: Full Text Search Webinar Questions Followup
August 24, 2012 By 5 Comments
…MySQL queries would make them even slower, I’m sure. Indeed, the result set of 20 rows from SphinxQL queries…data to the MySQL database or else periodically batch-insert data that has changed since last time … is a bit harder, because it’s quite costly to update an index incrementally — it’s …
Post: MySQL performance: Impact of memory allocators (Part 2)
March 8, 2013 By 12 Comments
Last time I wrote about memory allocators and how they can affect MySQL performance in general…, select_sum_ranges, point_select. Processing these queries will involve notable amount of malloc()/free() … allocators; it can notably boost your MySQL server at no cost. Also, an alternative allocator must…
Post: How expensive is a WHERE clause in MySQL?
October 31, 2008 By 17 Comments
… much overhead does a trivial WHERE clause add to a MySQL query? To find out, I set my InnoDB buffer pool…_date); insert into t select * from t; I repeated the last statement until it got slow enough that I thought I… up to about an extra 60% cost for the query. If I add another WHERE clause, mysql> select count(*) from t where a…
Post: Caching could be the last thing you want to do
July 24, 2010 By 14 Comments
… six sigma again) is to know what the miss path costs, but it is somewhat hidden. Cache management is really hard… every query? If you don’t, set long_query_time=0 and use mk-query-digest to capture queries. Run them through MySQL‘s EXPLAIN command. Do your queries SELECT…
