On Friday I gave a presentation on “MySQL Query Patterns, Optimized” for Percona MySQL Webinars. If you missed it, you can still register… SQL can produce an infinite variety of queries. The query optimizer analyzes queries for common patterns the MySQL designers know can be improved. But… between 47000 and 50000 with no movies, but your random number generator picks values in that range with equal frequency as…
Post: MySQL and the SSB - Part 2 - MyISAM vs InnoDB low concurrency
May 22, 2013 By Leave a Comment
… four sets of queries. Each set is known as a “flight”. I have labeled each query as Q{FLIGHT_NUMBER}.{QUERY_NUMBER}. In general, each… data. It seems that InnoDB performs better when a larger number of rows must be joined together (Q4.1, Q4.2… [mysqld] datadir=/mnt/mysql56/data basedir=/usr/local/mysql socket=/var/lib/mysql/mysql.sock user=justin innodb_buffer_pool_size=64G innodb…
Post: Percona Server 5.1.69-14.7 now available: A drop in replacement for MySQL
June 10, 2013 By 3 Comments
…_PAGES query started returning data to indicate an incomplete result set. Bug fixed #1185040. Fixed the upstream bug #69379 which caused MySQL clients to return bogus error number for host-not-found errors on Ubuntu 13… fixed #1184517. The INNODB_CHANGED_PAGES table couldn’t be queried if the log tracker wasn’t running. Bug fixed #1185304…
Post: Implementing SchemaSpy in your MySQL environment
June 4, 2013 By 2 Comments
…know the relationships between tables versus observing queries only. An additional benefit is that …6.10 sandbox: description=MySQL driver=com.mysql.jdbc.Driver connectionSpec=jdbc:mysql://127.0.0.1…tool. There are additional tabs: Tables – Names, number of children, parents, count of columns, row …
Post: Choosing a MySQL HA Solution - Post-Webinar Q&A
June 7, 2013 By Leave a Comment
… occurs. For example, if you see a large number of long-running queries in the output of SHOW PROCESSLIST that might be… simple query, but it’s always possible to build something more involved if that’s what you need. Q: What MySQL HA…: Incorrect information in file: ‘./mysql/servers.frm’ ERROR: 1033 Incorrect information in file: ‘./mysql/servers.frm’ Running mysql_install_db under strace, I…
Comment: Percona XtraBackup 2.1.3 for MySQL available for download
May 30, 2013 By 3 Comments
… may be invalid and cause the dump to abort. Query (0): is an invalid pointer Connection ID (thread ID):… of the crash. 130528 09:53:56 mysqld_safe Number of processes running now: 0 130528 09:53:56 …:56 mysqld_safe mysqld from pid file /var/lib/mysql/srv-d2-mysql02.pid ended in an another environment…
Post: Percona Playback 0.6 for MySQL now available
April 9, 2013 By 1 Comment
… another. Currently it can read queries from MySQL query-log and MySQL tcpdump files and run them on other MySQL server. With Percona Playback you… dispatching queries to MySQL database servers. This feature introduces new –thread-pool-threads-count option, which can be used to specify the number…
Post: More on MySQL transaction descriptors optimization
April 26, 2013 By Leave a Comment
… a followup by Dimitri Kravchuk, we have received a large number of questions on why the benchmark results in both posts… the first post: single SELECT queries doing PRIMARY KEY lookups (aka QPS sysbench mode); same MySQL queries executed inside single-statement transactions (TPS… perfect case for read-only transaction optimization in MySQL 5.6, because all SELECT queries in the AUTOCOMMIT mode are, by definition…
Post: High-load problems? Investigate them with 'pt-query-digest'
April 23, 2013 By 2 Comments
… is a little known goodie from Percona Toolkit for MySQL called pt-query-digest. One customer was suffering from periods of high…, but at least you get a nice ranking of queries sorted by the number of times they appear in processlist. In this…-format profile, to get just the ranking of queries. To my luck, one query stood out right away, always appearing many times…
Post: Percona Server for MySQL 5.5.30-30.2 now available
April 10, 2013 By 10 Comments
… on MySQL performance can be found in this blogpost. (Ignacio Nin) This release of Percona Server for MySQL has fixed a number of… query which opened that table. Bug fixed #1127008 (Sergei Glushchenko). Fix for bug #1070856 introduced a regression in Percona Server for MySQL… fixed #1015506 (Alexey Bychko). Percona Server for MySQL was missing help texts in the MySQL client because the help tables were missing…
