Message-ID: <78e4af96a4b34f1280ef96ddf347d5f7b8a53380.camel@cybertec.at>
Subject: Re: NUMA settings
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Marc =?ISO-8859-1?Q?Recht=E9?= <marc4@rechte.fr>,
	pgsql-performance@lists.postgresql.org
Date: Tue, 05 May 2020 10:25:57 +0200
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On Tue, 2020-05-05 at 10:11 +0200, Marc Rechté wrote:
> > I think that "vm.swappiness" should be 0.
> > PostgreSQL does its own memory management, any swapping by the kernel
> > would go against that.
> > 
> > Yours,
> > Laurenz Albe
> > 
> As said in the post, we wish the idle backends to be swapped out if 
> necessary. Therefore lowering swappiness would produce the opposite 
> effect: swapping out Linux file cache rather than backends memory.

I see.  Sorry for not paying attention.

An idle backend consumes only a few MB of RAM, though.

Yours,
Laurenz Albe
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