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Date: Thu, 28 Aug 2008 09:48:21 -0500
From: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
To: "Bill Moran" <wmoran@collaborativefusion.com>,
	"Matthew Wakeling" <matthew@flymine.org>
Cc: <pgsql-performance@postgresql.org>
Subject: Re: select on 22 GB table causes"An I/O error
	occured while sending to the backend." exception
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>>> Bill Moran <wmoran@collaborativefusion.com> wrote: 
> In response to Matthew Wakeling <matthew@flymine.org>:
>> 
>> Probably the best solution is to just tell the kernel somehow to
never 
>> kill the postmaster.
> 
> This thread interested me enough to research this a bit.
> 
> In linux, it's possible to tell the OOM killer never to consider
> certain processes for the axe, using /proc magic.  See this page:
> http://linux-mm.org/OOM_Killer
> 
> Perhaps this should be in the PostgreSQL docs somewhere?
 
That sure sounds like a good idea.
 
Even though the one time the OOM killer kicked in on one of our
servers, it killed a runaway backend and not the postmaster
( http://archives.postgresql.org/pgsql-bugs/2008-07/msg00105.php ),
I think I will modify our service scripts in /etc/init.d/ to pick off
the postmaster pid after a start and echo -16 (or some such) into the
/proc/<pid>/oom_adj file (which is where I found the file on my SuSE
system).
 
Thanks for the research and the link!
 
-Kevin