- it contains the text long semaphore wait
- it has text similar to the output SHOW INNODB STATUS
- connections wait too long for the adaptive hash latch (from btr0sea.c)
- a connection holds the adaptive hash latch -- search for holds adaptive hash latch
Saturday, October 25, 2008
In the unlikely case that there was a mysqld crash on servers that I use, a common cause was a long semaphore wait in InnoDB. MySQL bug 32149 has been open for this since November, 2007. We fixed this in our local branch, so this is rarely a problem for us now. The fixes are available in branches of MySQL 5.0 and 5.1 from Launchpad.