On Thu, Jan 02, 2003 at 10:30:50AM -0500, Michael Bacarella wrote: > Hi, > > Yesterday happened to be one of the busiest days for us ever on our > MySQL backed web site. For the entire day MySQL was hit with up to > 1200 queries/second, and many queries were being delayed at least > 2-15 seconds. We were serving about 300% of our normal load. > > In my opinion MySQL scaled more gracefully than I have ever known in > 4 years. It did not go into a downward spiral where once it went > above a threshold all work stopped. Instead, everything became > gradually slower, but still functioned albeit less quickly.
Woohoo! :-) > Right now I'm trying to figure out what bottlenecks the RDBMS was > hitting so we could throw some hardware at the problem. I am not > the kind of person to solve technical issues with hardware, but > given that nothing else appears to be wrong and I've done every > reasonable optimization possible, we have little choice. > > However, I can't figure out exactly why it was slow. Key efficiency > was at 100%, and I *believe* the InnoDB buffer pool was large enough > as the InnoDB monitor was reporting 1000 / 1000 cache hits. > > iostat showed the usual levels of disk I/O. > > What other statistics can I look at? > > We're using MySQL 3.23.54 > > Our hardware is dual P3 1GHz, 2GB of RAM, and about 56GB of IDE > RAID-1 backed disk (3ware escalade). Did you happen to get a snapshot of vmstat output or even iostat during that time? What's your ratio of read queries to write queries? Are you InnoDB or MyISAM tables more active? Are you using InnoDB transactions or running in auto-commit mode? One thing you can do is split things up a bit if I/O is a bottleneck. I like to put the InnoDB logs on separate disks from the data files. That way the log flushes don't fight with other disk activity. Jeremy -- Jeremy D. Zawodny | Perl, Web, MySQL, Linux Magazine, Yahoo! <[EMAIL PROTECTED]> | http://jeremy.zawodny.com/ MySQL 3.23.51: up 18 days, processed 648,609,824 queries (397/sec. avg) --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
