Qmail Support Forum

admin · Site Admin Joined: 21 Jun 2005 Posts: 210

Dear all

I am having a problem in my server slowing down ,while
mails send/received
at peak hours. More than 500 SMTP connections are
established at peak hours.

This is the /var/qmail/supervise/qmail-smptd/run file

#!/bin/sh
QMAILDUID=`id -u vpopmail`
NOFILESGID=`id -g vpopmail`
MAXSMTPD=`cat /var/qmail/control/concurrencyincoming`
exec /usr/local/bin/softlimit -m 6000000 \
/usr/local/bin/tcpserver -H -R -l 0 \
-x /home/vpopmail/etc/tcp.smtp.cdb -c "$MAXSMTPD"
\
-u "$QMAILDUID" -g "$NOFILESGID" 0 smtp \
/var/qmail/bin/qmail-smtpd bunix.com \
/home/vpopmail/bin/vchkpw /bin/true 2>&1

Today my server was fine in the morning but during
peak time , the smtp
connections increased and mailflow was also
increased.At this point ,
there was 480 SMTP connection and 300 mails in queue.
POP Connections was below 100 only.But many of the
outlook users were
not able to send mails. It was too slow to send mails
. Also the
total bandwidth of connection is 128 kbps The server
is having 1 GB of
RAM with PIII 700 GHZ processor.

In fact this server was upgraded from sendmail to
qmail. The above setup
with the same traffic and bandwidth was running
perfecly on 512 MB of RAM.
This surprises me.

Is sendmail better handle smtp connection than qmail
? or
Any fine tuning can be done on qmail-smtp or qmail?

Any help is appreciated.

Regds

Sridhar

admin · Site Admin Joined: 21 Jun 2005 Posts: 210

> MAXSMTPD=`cat /var/qmail/control/concurrencyincoming`
> exec /usr/local/bin/softlimit -m 6000000 \

if you calculate 480 * 6000000, you end up with
2.7 GB. how much does one of your qmail-smtpd processes
need memory, at max?