Andrew, DO you have the slow query log turned on? What does one of your tables look like and the one of the 8 queries you talk about? It very well could just be a index problem.
And what is the size of the data. Donny > -----Original Message----- > From: Andrew Nelson [mailto:[EMAIL PROTECTED] > Sent: Wednesday, December 01, 2004 11:22 PM > To: [EMAIL PROTECTED]; [EMAIL PROTECTED] > Subject: Re: Table Locking Problem? Very Slow MyISAM DB - PLS HELP! > > > >The reason I ask is because eight select statements should not bog down a > >production server. On the MySQL side, is anything being written to the > slow > >query log? On the application side is there any virus scanning or similar > >activity being performed? Does iostat show any heavy reading or writing > >activity? Is memory being swapped? What is the server load? Do you have a > >high wait time or is CPU usage the only symptom? > > Nothing is being written very often.. Maybe a few email accounts > added/modified each day. iostat shows very small disk activity > (around 0.4Mb/s average). No memory is being swapped.. > > We do have a high wait time - the email is queueing up and the website > interface to update the database (in PHP) times out when it's busy and > I figured it's the CPU - I don't get what is so computational, the > Databases > are quite small (it's just a userbase - about 200Kb). > > I appreciate your help, > Thanks, Andrew. > > > > > > > > >Andrew Nelson wrote: > > > >>Hi Victor, > >> > >> > >>>How did you deduce that the database server is the bottleneck? Are all > >>>your processes running on the same machine? > >> > >> > >>Because 'ps -aux' shows it running at 94% of the CPU and when I > >>stop/start the mysql server, it seems to be ok again for another > >>hour. > >> > >>Any ideas? > >> > >> > >>>Andrew Nelson wrote: > >>> > >>>>Hi, > >>>> > >>>>I have a MySQL 3.23.55 server managing accounts on my exim mail > server.. > >>>>The table type on all tables MyISAM.. I have the MTA performing > various > >>>>queries > >>>>for each incoming email - determining mail aliases, vacation messages > >>>>and > >>>>filtering rules etc but they're all pretty much SELECT statements.. I > >>>>know > >>>>this isn't ideal and i've started replacing runtime queries with > >>>>processes that > >>>>search text files instead (generated every few minutes etc) but it > >>>>should > >>>>still be able to cope I would have thought? > >>>> > >>>>At it's busiest, it's performing about 8 trivial queries per second. > >>>>It's a Xeon > >>>>2.6Ghz machine with 1Gb of RAM (running on FreeBSD) but it's grinding > to > >>>>a halt. > >>>> > >>>>I have to keep stopping and restarting the MySQL server to regain > speed. > >>>>As there's many processes trying to access the same tables to do > SELECTs > >>>>I > >>>>thought it might be a locking issue.. BDB didn't seem to help - can > >>>>anyone > >>>>suggest something that might help? > >>>> > >>>>Thanks, > >>>>Andrew. > >>>> > >>>> > >>>> > >>> > >> > > > > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: > http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
