[ On Saturday, March 20, 1999 at 15:09:26 (-0800), patl@??? wrote: ]
> Subject: Re: [EXIM] IMAP Servers
>
> Yes. I've been very happy with the Cyrus server. I particularly like
> the fact that it runs entirely as a non-privileged user, which eliminates
> many security concerns. (The downside is that it doesn't use the usual
> /var/mail spooling; so the only way to access your mail is via IMAP4 or
> POP3.)
That's actually an up-side if you have many users, especially if they
get lots of e-mail or "learn" to leave much e-mail on your server, and
even more especially if they can be "connected" all the time (eg. on a
local LAN, or a cable modem, or xDSL line, etc.).
Traditional POP and IMAP servers that simply read the traditional unix
spool file put a tremendous load on the system. We had a client with
several thousand active users who were leaving their mail clients
checking for new mail every few minutes or so 24x7 (I don't remember the
number of POP hits per minute, but it was fairly high). The big nasty
sparc ultra they were hitting against had a constant load average of
about 4-6 and its disk I/O was maxed out all the time. After they
switched to Cyrus the machine was nearly idle again.
Cyrus also implements mailbox quotas much more nicely than simple
filesystem quotas (though perhaps not as firmly -- I've not really
tested it strenuously).
--
Greg A. Woods
+1 416 218-0098 VE3TCP <gwoods@???> <robohack!woods>
Planix, Inc. <woods@???>; Secrets of the Weird <woods@???>
--
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