Message-ID: <5075BC09.8010006@optionshouse.com>
Date: Wed, 10 Oct 2012 13:18:49 -0500
From: Shaun Thomas <sthomas@optionshouse.com>
Reply-To: <sthomas@optionshouse.com>
Organization: Peak6
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To: Claudio Freire <klaussfreire@gmail.com>
CC: Bruce Momjian <bruce@momjian.us>, Julien Cigar <jcigar@ulb.ac.be>,
	<pgsql-performance@postgresql.org>
Subject: Re: shared_buffers/effective_cache_size on 96GB server
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On 10/10/2012 12:05 PM, Claudio Freire wrote:

> Why does nobody every mention that concurrent access has to be taken
> into account?

That's actually a good point. But if you have one giant database, the 
overlap of which tables are being accessed by various sessions is going 
to be immense.

There probably should be a point about this in the docs, though. There 
are more and more shared-hosting setups or places that spread their data 
horizontally across separate databases for various clients, and in those 
cases, parallel usage does not imply overlap.

-- 
Shaun Thomas
OptionsHouse | 141 W. Jackson Blvd. | Suite 500 | Chicago IL, 60604
312-444-8534
sthomas@optionshouse.com

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