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…
Comment: Joining many tables in MySQL - optimizer_search_depth
April 23, 2012 By 5 Comments
… ago, when I was just hired at MySQL. The assumptions about what are typical MySQL may have been true then in 2004…! = 5040, while 8! = 40320. The worst-case complexity of MySQL‘s join optimizer is N!. The goal of this choice was to… a conservative limit that guarantees that any query can be optimized quickly no matter how bad the pruning heuristics works. With…
Comment: Finding out largest tables on MySQL Server
April 24, 2012 By 24 Comments
… indicator that it may be a good opportunity to run OPTIMIZE and thus reclaim some hard disk space? Taking real-world…/lib/mysql/databasename # ls -lh tablename* -rw-rw—- 1 mysql mysql 8.7K 2010-08-05 16:31 tablename.frm -rw-rw—- 1 mysql mysql…
Post: Joining many tables in MySQL - optimizer_search_depth
April 20, 2012 By 5 Comments
… making it unusable to check the optimizer performance. Solution for this problem was to use set optimizer_search_depth=0, rarely used… further I found the following explanation from Timour Katchaounov in MySQL mailing list archives I have some recollection that there were… compatibility. In MySQL 5.6 things are likely to get even better handling joins of many tables as optimizer heuristics are improved…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
… comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a look at and benchmarking optimizer enhancements one… post is aimed at a new optimizer enhancement Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5…
Post: Webinar "How to Turbocharge Your MySQL Performance Using Flash Storage"
March 13, 2012 By 5 Comments
… we will cover: Configuration and optimization techniques to fully leverage flash-based storage solutions in MySQL environments Evaluation criteria and techniques for… storage is used appropriately for MySQL workloads Approaches for scaling MySQL instances on fewer servers while delivering optimal performance using flash drives The…
Post: How to Monitor MySQL with Percona's Nagios Plugins
February 22, 2012 By 8 Comments
… happen at inconvenient times. The pmp-check-mysql-file-privs plugin checks whether MySQL owns every file and directory within its data… down for a system reboot. The pmp-check-mysql-pidfile plugin verifies that MySQL‘s PID file exists. Evidence of contention in… allocating too much memory. A runaway server process, or poorly optimized queries, can consume too much memory and cause the server…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
… is targeted at the join related optimizations introduced in the optimizer. These optimizations are available in both MySQL 5.6 and MariaDB 5.5… made on MySQL 5.6 config: optimizer_switch=’index_condition_pushdown=off’ optimizer_switch=’mrr=on’ optimizer_switch=’mrr_cost_based=off’ optimizer_switch=’batched…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
… talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. This blog post is aimed at the optimizer enhancement Multi… about the MRR optimization available in MySQL 5.6 here: http://dev.mysql.com/doc/refman/5.6/en/mrr-optimization.html and as… the MySQL config: optimizer_switch=’index_condition_pushdown=off’ optimizer_switch=’mrr=on’ optimizer_switch=’mrr_sort_keys=on’ (only on MariaDB 5.5) optimizer…
Post: MariaDB 5.3 is released as GA!
March 5, 2012 By 17 Comments
… and MySQL 5.6 optimizer improvements, and both of them look very good indeed. Peter will present the results in an “optimizer standoff” talk at the upcoming MySQL conference, and Timour and Sergei from Monty Program… fix, and MySQL 5.6 offers microsecond timestamp support, as well as a lot of optimizer improvements. Even the standard MySQL 5.5…
