Message-ID: <ce7a0632877f187246a96bde9c41e590c8986703.camel@cybertec.at>
Subject: Re: WAL replay is too slow on secondary server
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Shubhang Joshi <shubhangjoshi2405@gmail.com>, OMPRAKASH SAHU
	 <sahuop2121@gmail.com>
Cc: pgsql-admin@lists.postgresql.org
Date: Thu, 30 Oct 2025 13:15:03 +0100
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On Thu, 2025-10-30 at 17:08 +0530, Shubhang Joshi wrote:
> On Thu, 30 Oct, 2025, 10:07=E2=80=AFam OMPRAKASH SAHU, <sahuop2121@gmail.=
com> wrote:
> > We have a postgresql cluster setup using patroni.
> > The DB is being used for heavy transactional application, now the probl=
em=C2=A0is that on replica server WAL replay is too slow.
> > We have increased the IOPS to 6k and Throughput to 600 on nvme EBS volu=
me of wal directory and 10k &800 on data directory.
> >=20
> > but the WAL is being accumulated on the replica as usual and applying w=
al is having no improvement.
>
> Please check the network speed =E2=80=94 we faced a similar issue earlier=
, and it turned out to be related to network performance.
> Kindly verify the network latency with your network team as well.

If WAL is piling up on the standby, how can network speed be the problem?

Yours,
Laurenz Albe