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Message-ID: <4B8D7A6C.3010304@gmail.com>
Date: Tue, 02 Mar 2010 21:51:56 +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
References: <cone.1267562557.293175.32557.1000@shelca>
In-Reply-To: <cone.1267562557.293175.32557.1000@shelca>
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Francisco Reyes wrote:
> Anyone has any experience doing analytics with postgres. In particular 
> if 10K rpm drives are good enough vs using 15K rpm, over 24 drives. 
> Price difference is $3,000.
>
> Rarely ever have more than 2 or 3 connections to the machine.
>
> So far from what I have seen throughput is more important than TPS for 
> the queries we do. Usually we end up doing sequential scans to do 
> summaries/aggregates.
>
With 24 drives it'll probably be the controller that is the limiting 
factor of bandwidth. Our HP SAN controller with 28 15K drives delivers 
170MB/s at maximum with raid 0 and about 155MB/s with raid 1+0. So I'd 
go for the 10K drives and put the saved money towards the controller (or 
maybe more than one controller).

regards,
Yeb Havinga