….g. pt-query-digest, pt-upgrade, and pt-online-schema-change). Here are some highlights: Official support for MySQL 5.6 and…-wait-timeout which set innodb_lock_wait_timeout because that now conflicts, or is at least confused with, lock_wait_timeout (introduced in MySQL… simpler pt-query-digest 2.2 has fewer options now. Basically, we re-focused it on its primary objective: analyzing MySQL query logs…
Post: Virident vCache vs. FlashCache: Part 2
May 17, 2013 By 3 Comments
…=0 –percentile=95 \ –mysql-user=root –mysql-socket=/tmp/mysql.sock –mysql-table-engine=innodb \ –oltp…not innodb options (fixed) back_log = 50 wait_timeout = 120 max_connections = 5000 max_prepared…4M thread_cache_size = 1000 query_cache_size = 0 query_cache_type = 0 ft_min_word…
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
… will summarize the output from the ./run_query command, called pivot_results cd shard-query/ $ ./run_query < queries.sql | tee raw |./pivot_results & [1…-recovery-update-relay-log innodb-replication-delay=# innodb-rollback-on-timeout innodb-rollback-segments=16 innodb-stats-auto-update=0 innodb…=256K tmp-table-size=64M transaction-isolation=READ-COMMITTED user=mysql wait-timeout=86400 To be continued You can now set up…
Post: MySQL Query Cache
July 27, 2006 By 70 Comments
… clarify what MySQL Query Cache is – I’ve seen number of people being confused, thinking MySQL Query Cache is the same as Oracle Query Cache – meaning cache where execution plans are cached. MySQL Query Cache is not… based or timeout based invalidation which can offer much better hit ratio for certain application. It is not that fast Query Cache…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
… to the amazing MySQL manual, especially the option and variable reference table…query_cache_limitblogpercona.commanual query_cache_min_res_unitblogpercona.commanual query_cache_sizeblogpercona.commanual query_cache_typeblogpercona.commanual query_cache_wlock_invalidateblogpercona.commanual query…
Post: Apache PHP MySQL and Runaway Scripts
May 20, 2008 By 20 Comments
… Apache Slot, MySQL Connection and other resources. I had discussion today who was thinking Apache would kill the script after “Timeout” specified… run checking “/Server-Status” checking if script dies after specified timeout. As the next step I pressed “STOP” button in the… sleep() function is wrong and if I would use real MySQL queries this would be counted to max_execution_time and so…
Post: Wishes for new "Pure PHP" MySQL driver
October 28, 2006 By 17 Comments
… for many applications. Query Timeouts Make it easy to specify timeouts for connects and query execution so page would not timeout but you would rather… in many cases. Multiple concurrent queries I would like to be able to run multiple queries for multiple MySQL connections at once. For…
Post: Implications of Metadata Locking Changes in MySQL 5.5
February 1, 2013 By 9 Comments
… bug: http://bugs.mysql.com/bug.php?id=67647 Metadata locking behaves differently for queries that are serviced from the Query Cache, let… Table Cache, any query to a table that has a DDL operation waiting, will block. Why? Because MySQL sees that the old… consequences. A workaround here would be to set lock_wait_timeout variable to a very low value and then execute the…
Post: How to debug long-running transactions in MySQL
March 8, 2011 By 6 Comments
… other transactions could block and fail with a lock wait timeout. The problem is, it can be very difficult to find… a while, use mk-query-digest to convert this into a query log, and examine the log. In MySQL 5.1 and newer… bringing everything on the system to a grinding “lock wait timeout” halt.
Post: How to Monitor MySQL with Percona's Nagios Plugins
February 22, 2012 By 11 Comments
… to deadlocks and timeouts, applications often don’t handle or log this error appropriately. The pmp-check-mysql-status plugin can be… that the server is alive and responds to a query. The pmp-check-mysql-status is also very flexible and can be… the incremental increase in a variable such as Queries and alert on a queries-per-second threshold. (I don’t suggest doing…
