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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 15:31:23 +0000"
Date: Tue, 17 Jan 2012 10:41:12 -0500
Message-ID: <16644.1326814872@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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=?UTF-8?Q?Mindaugas_=C5=BDak=C5=A1auskas?= <mindas@gmail.com> writes:
>> What about "psql -h localhost", ie physically local connection but
>> via TCP not unix socket?

> user@dbserver> psql -h 127.0.0.1 -p5432 -U user -W db

> This works fast. But

> user@dbserver> psql -h <IP> -p5432 -U user -W db

> (where <IP> is the multipath interface)

> This is slow! So it is definitely something network-related or
> something how PostgreSQL deals with multipath interface.

Hm.  AFAIR postgres doesn't know anything particular about multipath
interfaces --- it just listens where you tell it to.  So I'm thinking
this is a system-level issue.  It still seems like it could be DNS
lookup related though.  Do you have log_hostname turned on, and if so
does turning it off make a difference?

			regards, tom lane