Message-ID: <4DC85595.5070909@boreham.org>
Date: Mon, 09 May 2011 14:59:01 -0600
From: David Boreham <david_list@boreham.org>
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To: PGSQL Performance <pgsql-performance@postgresql.org>
Subject: Re: Benchmarking a large server
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> hm, if it was me, I'd write a small C program that just jumped
> directly on the device around and did random writes assuming it wasn't
> formatted.  For sequential read, just flush caches and dd the device
> to /dev/null.  Probably someone will suggest better tools though.
I have a program I wrote years ago for a purpose like this. One of the 
things it can
do is write to the filesystem at the same time as dirtying pages in a 
large shared
or non-shared memory region. The idea was to emulate the behavior of a 
database
reasonably accurately. Something like bonnie++ would probably be a good 
starting
point these days though.