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Need stand-alone ETRN program ▻

Speeding up SMTP servers

Followups to comp.mail.misc.

In article <gergDxwwnq.IEH@netcom.com>, Greg Andrews <gerg@netcom.com> wrote:
>I don't remember if my question was dealt with in the qmail docs,
>but the statement above suddenly makes me wonder if a write cache
>would help qmail-smtpd work faster.  (I'm picturing something like
>Sun's Prestoserve board)

Yes, a Prestoserve card should speed up qmail, as well as sendmail and
any other mail system.  It has a particularly dramatic effect on PP,
which makes at least two mkdir() calls, one directory rename() call, two
fsync() calls, and two rmdir() calls for every message it processes.

[ The Prestoserve card is a disk write cache with battery backup.
Synchronous write operations, like fsync() or mkdir(), only have to
wait for the data to reach the Prestoserve card, not the physical
disk.  If the system subsequently loses power, the write operation
will be completed by the Prestoserve card when the system reboots.
It's marketed as a go-faster device for NFS; I don't know the exact
details but a lot of NFS write operations (possibly even all) are done
synchronously by the server. ]

Tim.
--
Tim Goodwin   | "USENET, of course, is a pure and unadultered source
Cambridge, UK | of truth and wisdom." -- Richard Kettlewell

Original headers:

From: tim@pipex.net (Tim Goodwin)
Newsgroups: comp.mail.sendmail,comp.mail.misc
Subject: Re: Speeding up SMTP servers
Followup-To: comp.mail.misc
Date: 18 Sep 1996 14:57:32 GMT
Organization: UUNET PIPEX
Message-ID: <51p2ks$hqn@wave.news.pipex.net>
References: <1996Sep1701.35.08.18190@koobera.math.uic.edu>
  <gergDxwwnq.IEH@netcom.com>

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Need stand-alone ETRN program ▻