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From: Francisco Olarte <folarte@peoplecall.com>
Date: Thu, 30 May 2024 13:02:52 +0200
Message-ID: <CA+bJJbxT4S5hedrfBEzn2tDf650VLN8p6a6ey+QxSsctirtKBw@mail.gmail.com>
Subject: Re: Memory issues with PostgreSQL 15
To: =?UTF-8?Q?Christian_Schr=C3=B6der?= <christian.schroeder@wsd.com>
Cc: Muhammad Salahuddin Manzoor <salahuddin.m@bitnine.net>, 
	pgsql-general <pgsql-general@lists.postgresql.org>, Eric Wong <eric.wong@wsd.com>
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Hi christian:

On Thu, 30 May 2024 at 12:51, Christian Schr=C3=B6der
<christian.schroeder@wsd.com> wrote:
...
> I had already checked most of your points, but I double checked them now.
...
> Shared memory limits look good to me:
> # sudo sysctl -a | grep kernel.shm
> kernel.shmall =3D 18446744073692774399
> kernel.shmmax =3D 18446744073692774399
> kernel.shmmni =3D 4096

Bear in mind this is SysV shared memory. IIRC Pg uses POSIX shared
memory for shared buffers, which I think is backed normally in Linux
by files in a tmpfs mounted on /dev/shm. It still uses some amount of
SysV due to some special properties lacking from POSIX, for control
purposes, but only a little.

You could try "df -h /dev/shm" and "ls -lhR /dev/shm/" to see if you
have problems there.

Francisco Olarte.