Le 11/01/2010 01:13, Wietse Venema a écrit :
Patrick Chemla:
Wietse,
Please try the following, as asked half a week ago:
postconf -e smtp_connection_cache_on_demand=no
postfix reload
and report if this makes a difference.
Wietse
I have tested this since yesterday night.
I got some problems with Linux per user number of processes limit. I
fixed it. I also increased some delivery concurrency figures, and now I
can see up to 1300 processes delivering emails to the qmail servers.
I had a few minutes shot today at a rate of 6300 emails per minute. I
ran a full hour at 180,000 emails per hour. The outbound line was saturated.
CPU is about 30% loaded, no Wait I/O, no swap, memory is large.
I think I will reach about 600,000 emails per hour if I fix some timeout
on the qmails (replace by postfix?). Maybe I could reach 1 million?
OK, so you can turn back on that connection caching. Note that
qmail creates and destroys two processes per SMTP session, so
reusing a session is also a win from a CPU resource point of view.
Wietse
If I do so, will postfix open more than one connexion to each qmail for
parallel deliveries?
I am afraid that if we use connection caching this will create a single
queue on each qmail. As far as I have available resources, I think
prefer parallel deliveries.
Patrick
