Author: Edgar Lovecraft Date: To: exim-users Subject: Re: [Exim] calculating system requirements
As Wakko states below, most MTA servers, even with some additional duties,
can be run on fairly small servers. What I always figure out is how many
messages/day come through the current system (average and max), then
calculate how many messages I need to process in a minute to deliver that
email (then extrapolate what a 'best guess' would be for new hardware, as
this is what the 'current' system already supports). If the server is
running *nix, an MTA (w/ or w/out virus/spam scanning), caching DNS,
pop/imap, and possibly a webserver, with 2000 users or less, an old pentium
will usually do the job just fine. If you are looking at purchasing a
'new' system then going to your favorite computer provider and asking for
the $500.00 special should be more than enough. Most of the load for any
of our mail related servers is in the 'webmail' applications, not the
MTA/DB server(s). One note, The more memory you have, the better :)
--EAL--
> > I couldn't find anything on this. How do you calculate the system >
> requirements for both pop and imap mail with a MySQL or PostgreSQL >
> authentication backend (on the same computer)?
> >
> > For example, if you have a small office with 50 persons and need to >
> set up an imap mail system, how fast and how much memory and still > get
> reasonable performance. The same system would be running exim, > the
> imap softare, mysql and other support programs. Toss in needing >
> apache to run a webmail system such as IlohaMail, how does this > affect
> the system requirements?
>
> I'm running exim on a celeron 1.2ghz with 256mb ram and 20gb ide. It's
> not doing imap, just pop. It does have mysql server and all users are
> virtual. I tried to mvoe as much of the config to sql as possible. The
> userbase here is >200 users.
>
> The load of the machine doesn't often hit 1. It's also doing virus
> scanning (but not spam scanning. I don't like spam assassin) using
> mcafee. One thing is the users here don't seem to notice if there's a
> 1-2 second delay. I used to run the same setup on a dual pentium 233mmx,
> 256mb ram and 20gb hdd. Users still did not notice the speed difference
> after the upgrade.
> -- --