On 12/9/2010 3:21 PM, Wietse Venema wrote:
Dave Brodin:
We are an ISP and have Postfix running on FreeBSD. Currently, we are
using postfix 2.4.10 on FreeBSD 4.7. Both are older versions because
several years ago we tried to upgrade FreeBSD to 6.0 and had some
bizarre results. We just tried the same thing last night to a much
newer version of FreeBSD (8.2) with postfix 2.4.14 and had the same
results. I can't find any info on this behavior on the web, so here goes.
FWIW, FreeBSD is my primary development platform. I thought
that FreeBSD 8.1 is the latest release.
It's unlikely that a difference of four patchlevels for the same
Postfix major release causes radically different Postfix behaviors,
but you can easily verify this by running the same Postfix 2.4.10
binaries on FreeBSD 8 (this requires installing the misc/compat4x
package).
On the other hand there are major differences between FreeBSD 4.x
and 8.x. I am aware of major changes in the file system (introduced
with 5.x); multiprocessor support has changed dramatically from
5.x to 8.x, and lots of other internals were overhauled.
You need to find out what is thrashing your machine. From the
description it sounds like bad device driver software or hardware
controller, but such things can be verified with tools like vmstat,
iostat, etc. Look at I/O queues and time to satisfy I/O requests.
You can load-test Postfix off-line with tools such as smtp-source
or smtp-sink (bundled with Postfix source code).
Wietse
Thank you very much for the info. I'm really filling in because our
main system administrator's last day is tomorrow, unfortunately. I
guess it's 8.2-PRERELEASE (not sure how happy I am to find that out).
We did try 2.4.10 and it had the same problem.
I'll try the load testing tools. And it sounds like this is probably
better handled on the FreeBSD side.
--
Dave Brodin
