> One place that Rob and I still haven't found a good solution for profiling > is trying to work out whether we should be focussing on optimising our > mod_perl code, or our IMAP config, or our MySQL DB, or our SMTP setup, or > our daemons' code, or...
Assuming that the mod_perl app is the front-end for users and that you're trying to optimize for speed of responses, you should just use DProf to tell you which subroutines are using the most wall clock time. (I think it's dprofpp -t or something. Check the man page.) If the sub that uses IMAP is the slowest, then work on speeding up your IMAP server or the way you access it. CPU utilization may not be all that telling, since database stuff often takes the longest but doesn't burn much CPU. - Perrin
