> I have also posted this to vchkpw list: > > I have a server with qmail running some 600 email accounts over some > 30 domains. I recently installed simscan, Spamassassin and ClamAv. > It all works really well, but during peak hours (say 300 to 500k per > sec inbound traffic) Thee server starts to bog down and progressively > gets slower and slower until 120 connections are maxed out and the > server starts rejecting smtp connections first and then pop > connections. This is a new AMD 64 bit with 1Gig Ram running on > Debian and running also Apache with php, mysql, and Horde webmail > (with very very few hits per day). If I turn off simscan, situation > returns to normal after a while. I have tried finding some > documentation about how many users and traffic qmail with simscan, SA > and Clam may handle, but it seems there is nothing out there other > than very general stuff like "many users", "thousands of users".... > > Perhaps the problem is in my setup and some configuration for > simscan, SA or clam that I have set/not set incorrectly, ot I have > not realized this number of users and trafffic is just too much for > one server. Any suggestions or links to appropriate docs will be most > appreciated. > One thing that I found helpful was to put the simscan temporary directory onto a ramdisk. I have /var/qmail/simscan mounted as tmpfs, forcing the mode to 750, uid to simscan and gid to vchkpw (I use Vpopmail, YMMV), and specifying the size to 1G (my box has 1G ram and 2G swap, so the default tmpfs size is only 512M). Since anything put there is transient by definition, if I have a power failure and the contents die I lose nothing. And since simscan cleans up after itself, as long as you're not getting large numbers of very large emails all at once, it rarely forces the tmpfs to hit swap.
I actually have a server with the same memory config that runs 4 separate instances of qmail on separate IPs (consolidation of multiple servers into one box), and "idling" it only uses roughly half a gig of RAM. That's for 4 instances each of qmail and clamd, plus an assortment of other daemons used only for one instance or another and a MySql DB to hold it all together. It bogs down a little on occasion when a large list goes through, but that's all CPU from virus scanning hundreds of emails at once. One other suggestion - if you don't already use it, patch qmail with the external-todo patch - it speeds up send of mail while processing the queue... Josh -- Joshua Megerman SJGames MIB #5273 - OGRE AI Testing Division You can't win; You can't break even; You can't even quit the game. - Layman's translation of the Laws of Thermodynamics [EMAIL PROTECTED]
