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Date: Fri, 12 Mar 2010 11:19:38 +1100
Message-ID: <a056b1d41003111619v24353d5aodd1c1dfaaf0d251d@mail.gmail.com>
Subject: Re: shared_buffers advice
From: Paul McGarry <paul@paulmcgarry.com>
To: Ben Chobot <bench@silentmedia.com>
Cc: Postgresql Performance list <pgsql-performance@postgresql.org>
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On 11 March 2010 16:16, Ben Chobot <bench@silentmedia.com> wrote:

> I *can* say a 10GB shared_buffer value is working "well" with my 128GB of=
 RAM..... whether or not it's "optimal," I couldn't say without a lot of ex=
perimentation I can't afford to do right now. You might have a look at the =
pg_buffercache contrib module. It can tell you how utilized your shared buf=
fers are.

Thanks Ben and Greg,

I shall start with something relatively sane (such as 10GB) and then
see how we go from there.

Once this server has brought online and bedded in I will be updating
our other three servers which are identical in hardware spec and all
have the same replicated data so I'll be able to do some real world
tests with different settings withn the same load.

(Currently one is currently running postgresql 8.1 on 32bit OS under a
VM, the other two running 8.3 on 64bit OS with 64gig of memory but
with Postgres still tuned for the 8 gigs the servers originally had
and under a VM).

Paul