I have a problem with mysql 3.23.30-gamma. On the busy days with much
traffic on t he website, it hapens that suddenly mysql is taking all the
resources of the machine at very high speed. The swap increases quick,
the threads increase from about 30 (which is average) to over 70 and if
we don't stop mysql quickly, the computer stops responding. This happens
allways in the busiest hours of the day.
We are using mysql as database for a web site and use it in combination
with Apache::Session, which has a mechanism for locking session info
with GET_LOCK and RELEASE_LOCK.
At the moment that mysql is taking all the resources, apache is sending
many concurrent replies (about 45, relatively high), and after stopping
mysql (which can take long), several GET_LOCK-query appear in the
slow-query-logfile (about 20).
I have studied the problem several days, but can't find any clues so
far. I wonder whether the lock-mechanism could be the cause, or could it
be the consequence of a very very very heave query that never appears in
I hope you can give me answers to the following:
1. is there any known problem with GET_LOCK and RELEASE_LOCK in
version 3.23.30 ?
2. Is the GET_LOCK-mechanism the most suitable one to use with
3. Do you have any idea's what the problem could be or how to
investigate or how to solve ?
Herald van der Breggen
P.S. I upgraded today to version 3.23.31, so far without problems, but
the traffic very low at the moment.
|• locks, memory and threads||Herald van der Breggen||19 Jan|