Slow lmtpd

[Blake Hudson]

I would suggest starting by reviewing your memory usage (esp. swap) with
top and disk usage with "iostat -x 3" (part of the sysstat package)

More than likely you are running into problems in one of these areas.

-Blake


Andre Nathan wrote:
> Hello
>
> We have a cyrus server that runs under heavy load, and a few days ago it
> started to show a behaviour where its lmtpd processes take a long time
> to deliver messages sent from postfix. Below is an example of a postfix
> log message. with the email address removed:
>
> Feb 28 17:14:11 mta13 postfix/lmtp[9633]: 63CBA700071C:
> to=<user=domain.com at box2.prv.f3.k8.com.br>,
> relay=box2.prv.f3.k8.com.br[10.8.5.49]:2003, conn_use=6, delay=1718,
> delays=0.15/1118/0/600, dsn=4.4.2, status=deferred (conversation with
> box2.prv.f3.k8.com.br[10.8.5.49] timed out while sending end of data --
> message may be sent more than once)
>
> The last field in the "delays" field shows that the time out occurred
> after 600s trying to send the message to cyrus. Even when a timeout does
> not occur, the time for the message to be sent is around 100-300s.
>
> We have some other more lightly loaded servers in which the data is sent
> to lmtpd very quickly, and at any given moment there are only a few
> lmtpd's running. On the heavily loaded servers, there are always a few
> thousand lmtpd processes.
>
> I've run strace on lmtpd processes on both servers, and I couldn't spot
> any significative difference in their behaviours. They both run
> cyrus-imapd 2.2.12.
>
> So, I'm looking for some help and suggestions in trying to debug this
> situation, and maybe some tuning options to for lmtpd, or at least find
> out why they're taking so long to do complete the message delivery. The
> load on this server has always been pretty high, but this behaviour only
> started recently. It has much more mailboxes than the other server, as
> it mounts its volumes from a large AoE storage device.
>
> Thanks in advance,
> Andre
>
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