Wietse Venema:
> Patrick Chemla:
> > Le 08/01/2010 00:43, Victor Duchovni a ?crit :
> > > On Fri, Jan 08, 2010 at 12:30:34AM +0200, Patrick Chemla wrote:
> > >
> > >
> > >> Jan 7 22:02:57 postfix postfix/qmgr[26441]: 5B91F873F6: removed
> > >> Jan 7 22:02:57 postfix postfix/smtp[27180]: 375DDD5923:
> > >> to=<lexoti...@gmail.com>, relay=a139.localpc2105.com[10.0.0.139]:25,
> > >> conn_use=59, delay=61550, delays=17019/44435/96/0.17, dsn=2.0.0,
> ^^^^^^^^^^^
>
> Note that this connection has been reused multiple times (see below
> for what this means in Postfix).
>
> Why does it take 69 seconds to initialize a reused SMTP connection?
>
> What happens when you set
>
> smtp_connection_cache_on_demand=no
>
> in main.cf (and do "postfix reload")?
>
> If this makes a difference, then
Check your qmail configuration for "tarpit" options. There exist
qmail patches that will slow down the qmail SMTP server when the
client sends lots of email, or lots of recipients.
Wietse
> a) you have a problem with smtp<->scache communication.
>
> b) qmail does not like RSET commands
>
> c) Your machine is running low on memory and swapping out the scache
> process.
>
> d) something else.
>
> Wietse
>
> Under high load, smtp(8) processes give their open connections to
> scache(8). Later, they ask scache(8) for an open connection to a
> specific destination. Once an smtp(8) client retrieves an open
> connection, it sends RSET tothe remote server and waits for a 250
> reply (i.e. the server is still happy). According to the logfile
> record this lookup/rset/reply sequence is taking 96 seconds.
>
>
