…thanked by a lot of people running MySQL in wild. I also wanted… close connection MySQL can clean them up. Killing connections (or stopping related … Com_stmt_send_long_data to see whenever sending long data feature … better as you can query temporary tables too: mysql> select sum(data_length…
Post: Using LVM for MySQL Backup and Replication Setup
August 21, 2006 By 53 Comments
… to MySQL and run FLUSH TABLES WITH READ LOCK Note – this command may take a while to complete if you have long running queries. The… complete, even selects. So be careful if you have any long running queries. If you’re using only Innodb tables and do not…; 12) Run SLAVE START to restart replication. With slightly modified process you can clone slaves from the slaves without stopping them – you…
Post: How to Monitor MySQL with Percona's Nagios Plugins
February 22, 2012 By 8 Comments
…mysql-file-privs plugin checks whether MySQL owns every file and directory within its data directory. InnoDB is getting stuck, has long-running…open contention. Replication is delayed or stopped. Our plugins are structured to …a variable such as Queries and alert on a queries-per-second threshold. (I…
Post: 10+ Ways to Crash or Overload MySQL
November 13, 2007 By 20 Comments
… MySQL. The moment you give someone access to MySQL Server, all MySQL Security guarantees is you can stop… data for each of them using mysql_stmt_send_long_data call – Server buffers such data… variables for unprivileged user which allows to run queries with uncontrolled resource usage. Host Block You…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
…am constantly referring to the amazing MySQL manual, especially the option and variable reference table. But just…_tcblogpercona.commanual log_tc_sizeblogpercona.commanual log_warningsblogpercona.commanual long_query_timeblogpercona.commanual low_priority_updatesblogpercona.commanual lower_case_file_…
Post: Data mart or data warehouse?
July 15, 2010 By 13 Comments
…biggest parts of designing and running a data warehouse. A particular…this is because they provide one stop shopping for all the information… bitmap indexes, table partitioning, parallel query execution, clustered tables and materialized … on MySQL, but it is definitely possibly to use MySQL as long as…
Post: Apache PHP MySQL and Runaway Scripts
May 20, 2008 By 20 Comments
… or due to very complex query you can get your PHP script running too long, well after user stopped waiting for the page to… example you can open another MySQL connection to kill the query which was running (otherwise query may well continue to run even if PHP script… simple scripts which run for 1000 seconds (spending this time on MySQL time) one is doing single query another 1000 queries 1 second length…
Post: Living with backups
November 6, 2008 By 28 Comments
… same block again. That happens for as long as it does not get flushed. MySQL obviously takes advantage of this functionality just… that running a simple copy operation from MySQL data directory will result in a total disaster after MySQL stops responding to the incoming queries quick…
Post: The two even more fundamental performance metrics
May 5, 2011 By 6 Comments
…process and send back the response, with a “long tail” of requests that take longer than … This is common in MySQL servers I work with when they’re running a simple read-mostly …would normally be sending queries to the server would be stopped, waiting for existing queries to complete. That didn…
Post: Top 5 Wishes for MySQL
June 29, 2007 By 10 Comments
…MySQL 4.1 but you still could not run (and still can’t) most of your Oracle/DB2/MS SQL Queries on MySQL…very long time. For example Query Cache support for Prepared Statements is only fixed in MySQL 5…suggested by MySQL customers and myself based on long MySQL usage for Web. Later I stopped adding …
