To: "Csaba Nagy" <nagy@ecircle-ag.com>
Cc: "Decibel!" <decibel@decibel.org>,  <pgsql-performance@postgresql.org>
Subject: Re: Linux mis-reporting memory
In-Reply-To: <1190363401.4661.116.camel@PCD12478> (Csaba Nagy's message of
	"Fri\, 21 Sep 2007 10\:30\:01 +0200")
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References: <20070920230400.GM95343@decibel.org>
	<16213.1190329934@sss.pgh.pa.us> <87r6ksa1jb.fsf@oxford.xeocode.com>
	<1190363401.4661.116.camel@PCD12478>
From: Gregory Stark <stark@enterprisedb.com>
Organization: EnterpriseDB
Date: Fri, 21 Sep 2007 10:43:07 +0100
Message-ID: <87r6ksuzf8.fsf@oxford.xeocode.com>
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"Csaba Nagy" <nagy@ecircle-ag.com> writes:

> On Fri, 2007-09-21 at 09:03 +0100, Gregory Stark wrote:
>> >> Mem:  32945280k total, 32871832k used,    73448k free,   247432k buffers
>> >> Swap:  1951888k total,    42308k used,  1909580k free, 30294300k cached
>> >
>> It seems to imply Linux is paging out sysV shared memory. In fact some of
>> Heikki's tests here showed that Linux would do precisely that.
>
> But then why is it not reporting that in the "Swap: used" section ? It
> only reports 42308k used swap. 

Hm, good point.

The other possibility is that Postgres just hasn't even touched a large part
of its shared buffers. 

-- 
  Gregory Stark
  EnterpriseDB          http://www.enterprisedb.com