…queries. Following that there are summaries of various data points such as the total query execution time and the average query execution time…queries that you can use to gather more data about the underlying tables involved and the query execution plan used by MySQL…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
Post: Checking for a live database connection considered harmful
May 5, 2010 By 38 Comments
…’ or ‘statistics‘ command at the MySQL protocol level, which will increment Com_admin_commands in SHOW GLOBAL STATUS, or a trivial query such… to the application of the network round-trip plus the query execution time, and the added load on the database server. The added… these silly queries: # Rank Query ID Response time Calls R/Call Item # ==== ================== ================ ====== ======== =============== # 1 0x5E796D5A4A7D1CA9 10651.0708 73.1% 120487 0.0884 ADMIN STATISTICS # 2…
Post: When Does InnoDB Update Table Statistics? (And When It Can Bite)
October 6, 2011 By 7 Comments
… the MySQL optimizer choose the appropriate index for a query. If a table’s statistics or index cardinality becomes outdated, you might see queries… STATUS FROM schema taking away a couple of seconds on execution time. # Time: 110923 1:48:17 # User@Host: user1[user1] @ [172.20…
Post: How to convert MySQL's SHOW PROFILES into a real profile
February 20, 2012 By 12 Comments
…time MySQL spends in various phases of query execution…
Post: Shard-Query turbo charges Infobright community edition (ICE)
May 6, 2011 By 23 Comments
… decent amount of time, but not so large that it was difficult to work with. The ontime flight performance statistics data, available… machines. Baseline: The MySQL command line client was used to execute the a script file containing the 11 queries. This same SQL script… the Shard-Query tests. For the baseline, the results and response times were captured with the T command. The queries were executed on a…
Post: Announcing Percona Playback 0.5
November 26, 2012 By
…mysql-username=root –mysql-password=passW0rd –mysql-schema=imdb This example uses accurate tcpdump-mode, which means Percona Playback will preserve query execution times…
Post: MySQL Upgrade Webinar Questions Followup
June 28, 2012 By 7 Comments
…Query Execution…time so other has full resources (including memory) available. Another thing to mention having multiple instances of different MySQL…
Post: MySQL 5.6.10 Optimizer Limitations: Index Condition Pushdown
March 14, 2013 By 2 Comments
… in the field note. The original query had a stable execution time of 1.09 sec, while the … of the current query planner. However I would like to see better algorithms, statistics computation and…and technical opinion about the new features of MySQL query planner? Are you not yet familiar with…
Post: Auditing login attempts in MySQL
December 28, 2012 By 4 Comments
…mysql> select * from user_statistics where user=’root’\G *************************** 1. row *************************** USER: root TOTAL_CONNECTIONS: 25 CONCURRENT_CONNECTIONS: 0 CONNECTED_TIME: 464 BUSY_TIME…time, bytes received and sent, rows accessed, commands executed…
Post: Troubleshooting MySQL Upgrade Performance Regressions
February 15, 2012 By Leave a Comment
…runs this query concurrently many times or even workload consisting of several query types. Though…MySQL Server versions you should: Check Query Plan Run EXPLAIN to see if plans for the query are the same. Changing Query Execution… TABLE on both MySQL Versions to see if you can get statistics to be …
