From: Tom Lane <tgl@sss.pgh.pa.us>
To: Gurjeet Singh <gurjeet@singh.im>
cc: Andres Freund <andres@2ndquadrant.com>,
 Peter Eisentraut <peter_e@gmx.net>,
 PGSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: /proc/self/oom_adj is deprecated in newer Linux kernels
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Comments: In-reply-to Gurjeet Singh <gurjeet@singh.im>
 message dated "Tue, 10 Jun 2014 10:45:50 -0400"
Date: Tue, 10 Jun 2014 11:29:58 -0400
Message-ID: <30893.1402414198@sss.pgh.pa.us>
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Sender: pgsql-hackers-owner@postgresql.org

Gurjeet Singh <gurjeet@singh.im> writes:
> As it stands right now, a user can decrease the likelyhood of
> Postmaster being killed by adjusting the start script, but that
> decreases the likelyhood of al the child processes, too, making the
> Postmaster just as likely as a kill-candidate, maybe even higher
> because it's the parent, as any backend.

Exactly.

> This patch gives the user a control to let the backend's likelyhood of
> being killed be different/higher than that of the postmaster.

If you think your users might want to give the postmaster OOM-exemption,
why don't you just activate the existing code when you build?  Resetting
the OOM setting to zero is safe whether or not the startup script did
anything to the postmaster's setting.

In short, I don't see what a GUC adds here, except uncertainty, which
is not a good thing.

			regards, tom lane


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