On Wed, May 22, 2013 at 04:45:42PM +0300, Selcuk Yazar wrote:
> > >If your content filter is not very fast, bursts of mail will accumulate<
> > >while they are waiting to be scanned. Then the queue becomes empty.
> > >
> > >You may also have deferred mail that is retried periodically. You logs
> > >have a more complete picture.
> > >
> > >To improve content filter performance, eliminate remote DNS lookups
> > >in the filter, or increate concurrency. If the problem is lack of
> > >sufficient CPU resources, try to find a more performant scanner or
> > >turn off optional scanning features you don't need.
> > >
> > >Since mail is not delayed for very long, there is no problem (certainly
> > >not with Postfix itself, but scanning could perhaps be tuned).
>
> I found a script for log analyze (sourceforge), result are like below. I
> think we have some queue problem, as I understand, %95 e-mails wait in
> queue 132 seconds ?
No, less than 5% of messages spend more than 132s in the active
queue. Most messages spend less than 21s, with 50%s delivered
immediately.
> postfix logwatch
>
> === Delivery Delays Percentiles
> ============================================================
> 0% 25% 50% 75% 90% 95%
> 98% 100%
> --------------------------------------------------------------------------------------------
> In qmgr 0.00 0.00 0.01 21.00 110.00 132.00
> 158.00 180.00
> Conn setup 0.00 0.00 0.00 0.00 0.85 9.43
> 51.00 226.00
> Transmission 0.00 0.11 4.70 6.20 13.00 18.00
> 22.00 73.00
> Total 0.04 1.10 9.00 46.00 123.00 154.00
> 180.00 2373.00
> ============================================================================================
To understand what is actually going on, you'll have to *read* the
logs, not just look at summaries. You'll probably find occasional
latency sending messages through the content filter. If that's a
problem, tune the content filter to remove DNS lookups or raise
its concurrency. If the content filter is using all available CPU
resources, tune it to do less, or find a more efficient one.
Before any of that, locate the log entries showing delayed deliveries,
read them, and figure out the reasons for the delay.
--
Viktor.
