From: Listaccount <lst_hoe01@kwsoft.de>
To: pgsql-admin@postgresql.org
Subject: Dangerous hint in the PostgreSQL manual
Date: Mon, 10 Dec 2007 16:26:12 +0100
Message-ID: <20071210162612.a9y113hzjkookooc@webmail.kwsoft.de> (raw)
Hello
I have been trapped by the advice from the manual to use "sysctl -w
vm.overcommit_memory=2" when using Linux (see 16.4.3. Linux Memory
Overcommit). This value should only be used when PostgreSQL is the
only Application running on the machine in question. It should be
checked against the values "CommitLimit" and "Committed_AS" in
/proc/meminfo on a longer running system. If "Committed_AS" reaches or
come close to "CommitLimit" one should not set overcommit_memory=2 (see
http://www.redhat.com/archives/rhl-devel-list/2005-February/msg00738.html). I
think it should be included in the manual as a warning because with
this setting the machine in question may get trouble with "fork
failed" even if the standard system tools report a lot of free memory
causing confusion to the admins.
Regards
Andreas
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To: pgsql-docs@postgresql.org
Cc: lst_hoe01@kwsoft.de, pgsql-admin@postgresql.org
Subject: Re: Dangerous hint in the PostgreSQL manual
In-Reply-To: <20071210162612.a9y113hzjkookooc@webmail.kwsoft.de>
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