From: Tom Lane <tgl@sss.pgh.pa.us>
To: Thomas Kellerer <shammat@gmx.net>
cc: pgsql-admin@lists.postgresql.org
Subject: Re: PostgreSQL local connection is taking 4 seconds
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Comments: In-reply-to Thomas Kellerer <shammat@gmx.net>
	message dated "Tue, 02 Jan 2024 16:55:00 +0100"
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Date: Tue, 02 Jan 2024 11:27:26 -0500
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Thomas Kellerer <shammat@gmx.net> writes:
> pramod kg schrieb am 02.01.2024 um 14:58:
>> We have upgraded the OS from RHEL7 to RHEL8 in our testbed machines. Af=
ter upgrading, PostgrSQL=C2=A0local connection is taking ~4 seconds (Both =
TLS and non TLS connection). Please advise on what to be verified? There i=
s no change in postgresql.conf or pg_hba.conf.

> Did you enable log_hostname?
> That does a revers DNS lookup which could be a reason for the connection=
 suddenly taking longer.

Even without log_hostname, it could be a slow-DNS-lookup problem.

Rather than guessing, though, it might be time to try strace'ing
the psql session to see what it's waiting for.

			regards, tom lane