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Message-ID: <4B8E2FA9.4010109@gmail.com>
Date: Wed, 03 Mar 2010 10:45:13 +0100
From: Yeb Havinga <yebhavinga@gmail.com>
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To: Francisco Reyes <lists@stringsutils.com>
CC: Pgsql performance <pgsql-performance@postgresql.org>
Subject: Re: 10K vs 15k rpm for analytics
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Francisco Reyes wrote:
>
> Going with a 3Ware SAS controller.
>
>
> Have some external enclosures with 16 15Krpm drives. They are older  
> 15K rpms, but they should be good enough.
> Since the 15K rpms usually have better Transanctions per second I will 
> put WAL and indexes in the external enclosure.

It sounds like you have a lot of hardware around - my guess it would be 
worthwhile to do a test setup with one server hooked up with two 3ware 
controllers. Also, I am not sure if it is wise to put the WAL on the 
same logical disk as the indexes, but that is maybe for a different 
thread (unwise to mix random and sequential io and also the wal has 
demands when it comes to write cache).

regards,
Yeb Havinga