To: =?UTF-8?Q?Mindaugas_=C5=BDak=C5=A1auskas?= <mindas@gmail.com>
cc: pgsql-admin@postgresql.org
Subject: Re: Establishing remote connections is slow 
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Comments: In-reply-to =?UTF-8?Q?Mindaugas_=C5=BDak=C5=A1auskas?=
	<mindas@gmail.com> message dated "Tue, 17 Jan 2012 12:44:26 +0000"
Date: Tue, 17 Jan 2012 10:09:42 -0500
Message-ID: <15697.1326812982@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

=?UTF-8?Q?Mindaugas_=C5=BDak=C5=A1auskas?= <mindas@gmail.com> writes:
> I have a very weird problem related to establishing remote connections
> to PostgreSQL server and hopefully someone can give me some hints how
> can I debug this.

> The essence is that establishing remote connection takes anywhere from
> 10 to 30 seconds. Once connected, the queries are fast - it's just
> establishing new connection that takes ages.

Perhaps the problem is related to authentication - what auth mode
are you using, and can you experiment with some other ones?

What I'd do to start debugging this is to get out a packet sniffer
(wireshark or some such) and just observe the timings of packets sent
and received by Postgres.  This would at least give you a hint which
step is the bottleneck.

> This problem is not
> applicable to establishing local connections: running psql command
> from the local machine takes no time to connect, same applies if a
> client connects to the PostgreSQL via ssh tunnel.

What about "psql -h localhost", ie physically local connection but
via TCP not unix socket?

			regards, tom lane