----- Original Message -----
From: "Wietse Venema" <[email protected]>
To: "Brandon Hilkert" <[email protected]>
Cc: "Wietse Venema" <[email protected]>; <[email protected]>
Sent: Friday, March 20, 2009 12:45 PM
Subject: Re: Performance tuning
Brandon Hilkert:
>> and when I send a mail, postfix says there's not enough space in the
>> queue.
>> Should I be doing it a different way?
>
> Postfix requires that the amount of space is several times larger
> than the message size limit
>
> http://www.postfix.org/postconf.5.html#queue_minfree
> http://www.postfix.org/postconf.5.html#message_size_limit
I was able to get it to mount to tmpfs and it showed no change in
performance, so that would theoretcially rule out any existing disk issue
right?
tmpfs is backed by the swap file, which is on disk.
>> My disk is writing about 3 MB/s which should be well within it's
>> range. I
>> would hope even larger, but I would like to work out the ramfs and
>> test
>> for
>> sure.
>
> Bitrates are completely irrelevant.
what is best to look out and compare?
When the disk is 100% busy, then it is the bottle neck. Disks can
be 100% busy jumping around doing very little I/O.
As Noel suggested in earlier email, try running smtp-sink which
does no disk I/O at all. If things are still slow, then the problem
is network or MS-Exchange configuration.
I found the source. How do I build it in Debian? I realize this is probably
a stupid question, but I don't have tons of experience with Linux.
Exchange hasn't been involved at all. I've been running everything from
scripts, hoping to zero in on the bottleneck.
Wietse
