Couple of thoughts ... lsof -p <pid of mysql process> may give some clue of what files/tables it's reading/writing. From that you may be able to deduce something useful.
Check the slow query log and see if any of the queries are CPU-intensive (by doing an EXPLAIN) and are the bottleneck. - Ashish On Fri, Aug 20, 2010 at 10:09 PM, Tom Kleinpeter <tomkleinpe...@gmail.com>wrote: > I've been watching our mysqld procs in htop and the root thread is > using 75-100% of a CPU most of the time. I'm trying to understand > what that is being used for, and so I was hoping someone could tell me > what that thread does that might be using a lot of CPU. > > We are using 5.5.4-m3, we use MyISAM tables with full text indexes, do > around 1500-2000 queries per second, accept around 150 connections per > second, and at the moment both our key cache and our query cache are > disabled (I was curious if that contention was an issue). CPU usage > didn't really change with the caches disabled. > > The server is doing around 2 megabytes of traffic per second. We > store a bunch of data compressed, and use "uncompress(columnName)" in > queries to get it back out. None of these things set off any red > flags for me, but it has been a number of years since I've tuned > MySQL, so I don't really trust myself. > > Thanks, > Tom > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: > http://lists.mysql.com/mysql?unsub=ashish.mukher...@gmail.com > >
