Message-ID: <4BCE9F23.1080000@2ndquadrant.com>
Date: Wed, 21 Apr 2010 02:45:55 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: David Kerr <dmk@mr-paradox.net>
CC: Scott Marlowe <scott.marlowe@gmail.com>,
	Nikolas Everett <nik9000@gmail.com>,
	Robert Haas <robertmhaas@gmail.com>, pgsql-performance@postgresql.org
Subject: Re: Very high effective_cache_size == worse performance?
References: <20100420173936.GA50886@mr-paradox.net>
	<h2w603c8f071004201044tbc8ce8fenb846b7643a2b9376@mail.gmail.com>
	<20100420180351.GA51940@mr-paradox.net>
	<w2ld4e11e981004201112v3571f350zaaa0112d1e035097@mail.gmail.com>
	<20100420182030.GA53489@mr-paradox.net>
	<j2qdcc563d11004201123u21219445v4a9129ee7d7b520b@mail.gmail.com>
	<20100420182832.GB53489@mr-paradox.net>
	<4BCE0E0C.1020903@2ndquadrant.com>
	<20100420203919.GA62103@mr-paradox.net>
In-Reply-To: <20100420203919.GA62103@mr-paradox.net>
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David Kerr wrote:
> I don't think it's anything in the Db that's causing it. ( drop and re-create
> the db between tests) I actually suspect a hardware issue somewhere. 
>   

You might find my "Database Hardware Benchmarking" talk, available at 
http://projects.2ndquadrant.com/talks , useful to help sort out what's 
good and bad on each server, and correspondingly what'd different 
between the two.  Many of the ideas there came from fighting with SAN 
hardware that didn't do what I expected.

-- 
Greg Smith  2ndQuadrant US  Baltimore, MD
PostgreSQL Training, Services and Support
greg@2ndQuadrant.com   www.2ndQuadrant.us