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From: Jonathan de Boyne Pollard <J.deBoynePollard-newsgroups@NTLWorld.com>
Subject: Re: syslogd(8) with OOM Killer protection
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Date: Sun, 31 Jan 2016 13:35:30 +0000
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Torsten Zuehlsdorff:

 > I would like a generalized way too. The first i thought to protect is 
my database. I never want to get it killed.


You might enjoy this view on OOM Killers, then:

* http://thoughts.davisjeff.com/2009/11/29/linux-oom-killer/


A widely circulated postgresql.service unit for systemd gained this a 
couple of years later:

 > # Due to PostgreSQL's use of shared memory, OOM killer is often 
overzealous in

 > # killing Postgres, so adjust it downward

 > OOMScoreAdjust=-200


Discounting 200 permil of a process' memory use, when the known problem 
is that that process shares a lot of its memory with its children, seems 
slightly conservative.