Message-ID: <f393ed522208b1253be393eaf7c66b4637e4d059.camel@cybertec.at>
Subject: Re: problem during postgres restore: max_connections = 100 is a
 lower setting than on the primary server, where its value was 350
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Fabrice Chapuis <fabrice636861@gmail.com>, Pgsql-admin
	 <pgsql-admin@lists.postgresql.org>
Date: Mon, 02 Mar 2026 18:42:52 +0100
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On Mon, 2026-03-02 at 17:13 +0100, Fabrice Chapuis wrote:
> I think the value of max_connections must be aligned with primary because
> the goal is to maintain this sizing in case of a failover and promotion o=
f the standby.

Not every standby is for failover.
The technical reason is that the process array on the standby has to be at =
least
as big as on the primary (if you are setting "hot_standby =3D on").

> Why to be conservative with `max_connection` and not with shared buffer?
> If we're performing recovery on a machine with significantly fewer CPU an=
d RAM
> resources than the original server, lowering these parameters could be an=
 option
> because they reserve memory at starting.

Perhaps, but you cannot do it.  If that is a requirement, use a connection =
pool.

Yours,
Laurenz Albe