[BlueOnyx:24044] Re: 5210R - Delay in postfix processing/delivery

[Michael Stauber]

Hi Dirk,

> Thank you very much for the explanations.

The AV-SPAM 7.1.1-1 for 5210R has just been released. It fixes the issue
that spamass-milter would (if Postfix was used) scan outbound emails as
well. Regardless if that was enabled in the GUI or not. This update
fixes that.

> Hmm but I thought I had disabled the spamassassin milter for 
> postfix and then it would have taken just as long... but i can be
> wrong. In any case I'm curious about the behaviour after the update.

I just did some testings from RoundCube on a 5210R. I've sent three
identical emails to the same recipient address on the listserver.

AV-SPAM completely disabled:

to=<ms at blueonyx.it>, relay=mail.blueonyx.it[208.77.151.199]:25, delay=8,
delays=5.1/0.06/0.15/2.7, dsn=2.0.0, status=sent (250 2.0.0
05QKMxeg029416 Message accepted for delivery)

AV-SPAM outbound scans with SpamAssassin enabled:

to=<ms at blueonyx.it>, relay=mail.blueonyx.it[208.77.151.199]:25,
delay=9.7, delays=6.4/0.07/0.45/2.7, dsn=2.0.0, status=sent (250 2.0.0
05QLNABo018366 Message accepted for delivery)

AV-SPAM: Outbound scans with SpamAssassin disabled:

to=<ms at blueonyx.it>, relay=mail.blueonyx.it[208.77.151.199]:25,
delay=8.1, delays=5.2/0.06/0.2/2.7, dsn=2.0.0, status=sent (250 2.0.0
05QLS2j5018411 Message accepted for delivery)

Each of these transactions took over 8 seconds to complete. Regardless
of the AV-SPAM or its configuration. The SpamAssassin check (if enabled
on outbound emails) added roughly another second, but in the great
scheme of things it didn't matter much.

As for understanding these Postfix "delay" entries in the maillog:

Postfix logs additional delay information as "delays=a/b/c/d" where ...

a=time before queue manager, including message transmission;
b=time in queue manager;
c=connection setup time including DNS, HELO and TLS;
d=message transmission time.

The biggest delay we're seeing in all three scenarios above is the
"a=time before queue manager, including message transmission". Five
seconds for that seems awfully long.

I don't yet have an idea how we can tweak that. Any Postfix gurus around?

-- 
With best regards

Michael Stauber