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POMySQL SET timestamp as a Slow Query
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copied!<blockquote> <p><strong>Possible Duplicate:</strong><br> <a href="https://stackoverflow.com/questions/2832912/how-can-set-timestamp-be-a-slow-query">How can “set timestamp” be a slow query?</a> </p> </blockquote> <p>I am running a web application and Wordpress blog using PHP and MySQL 5.1, residing on a VPS server. The slow query log is showing many entries for items that should not be taking very long to complete. The strange thing is that it when I click on my blog link, it usually take a long time to load initially, but after that it is pretty quick. Then in a few hours it is back to the slow first click again. It seems as if the "SET timestamp= " query is present in nearly all of the slow entries. Here is an example of what it looks like:</p> <pre> # Time: 110129 4:02:06 # User@Host: appsadmin[appsadmin] @ localhost [] # Query_time: 1.367264 Lock_time: 0.000043 Rows_sent: 18 Rows_examined: 18 use apps; SET timestamp=1296291726; show tables; # Time: 110129 4:02:07 # User@Host: wp_user[wp_user] @ localhost [] # Query_time: 0.635450 Lock_time: 0.000041 Rows_sent: 11 Rows_examined: 11 use wordpress_user; SET timestamp=1296291727; show tables; # Time: 110130 4:02:03 # User@Host: appsadmin[appsadmin] @ localhost [] # Query_time: 0.592159 Lock_time: 0.000000 Rows_sent: 0 Rows_examined: 0 use apps; SET timestamp=1296378123; SELECT /*!40001 SQL_NO_CACHE */ * FROM `mail_queue`; # Time: 110131 4:02:08 # User@Host: appsadmin[appsadmin] @ localhost [] # Query_time: 2.789990 Lock_time: 0.000047 Rows_sent: 18 Rows_examined: 18 SET timestamp=1296464528; show tables; # Time: 110131 4:02:09 # User@Host: wp_user[wp_user] @ localhost [] # Query_time: 0.535981 Lock_time: 0.000041 Rows_sent: 11 Rows_examined: 11 use wordpress_user; SET timestamp=1296464529; show tables; # Time: 110201 3:19:03 # User@Host: wp_user[wp_user] @ localhost [] # Query_time: 1.401393 Lock_time: 0.000071 Rows_sent: 120 Rows_examined: 145 SET timestamp=1296548343; SELECT option_name, option_value FROM wp_options WHERE autoload = 'yes'; </pre> <p>This shows that it is not an issue with my DB design, but some kind of configuration problem.</p>

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