Re: Bizarre delays in mailing list messages

Tom Lane wrote:
> Since the cutover in mailing list servers a few months ago, I've been
> noticing that some messages suffer unexpected delivery delays,
> particularly on the pgsql-committers list.  An example today was that
> I pushed two patches to three different branches at approximately 16:39
> UTC.

Hmm, yeah, I see that malur wimped out of sending a couple of those
timely due to high system load:

2012-10-17 16:39:48 1TOWeq-0004di-GZ <= pgsql-committers-owner+M49504=tgl=sss.pgh.pa.us@postgresql.org H=localhost
(postgresql.org)[127.0.0.1] P=smtp S=4405 id=E1TOWeC-0007fb-Eu@gemulon.postgresql.org 
2012-10-17 16:39:48 1TOWeq-0004di-GZ no immediate delivery: load average 10.54
2012-10-17 16:46:18 1TOWeq-0004di-GZ => tgl@sss.pgh.pa.us R=dnslookup T=remote_smtp H=sss.pgh.pa.us [66.207.139.130]
2012-10-17 16:46:18 1TOWeq-0004di-GZ Completed

2012-10-17 16:39:47 1TOWep-0004da-Ho <= pgsql-committers-owner+M49507=tgl=sss.pgh.pa.us@postgresql.org H=localhost
(postgresql.org)[127.0.0.1] P=smtp S=3831 id=E1TOWeC-0007fV-Bi@gemulon.postgresql.org 
2012-10-17 16:39:47 1TOWep-0004da-Ho no immediate delivery: load average 10.54
2012-10-17 17:01:02 1TOWep-0004da-Ho => tgl@sss.pgh.pa.us R=dnslookup T=remote_smtp H=sss.pgh.pa.us [66.207.139.130]
2012-10-17 17:01:02 1TOWep-0004da-Ho Completed

This is not specific to pgsql-committers in any way; I see a lot of
messages delayed like that at particular points in time.  When we did
the migration, we discussed the idea of having a secondary delivery
helper server, but in the interest of keeping things simple we stayed
away from it then.  We will need to discuss it to figure out the best
way to deal with it.

Thanks for pointing it out.

--
Álvaro Herrera                http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services