Message-ID: <4C44635D.7080601@2ndquadrant.com>
Date: Mon, 19 Jul 2010 10:38:21 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: Daniel Ferreira de Lima <dfl.man@gmail.com>
CC: Kevin Grittner <Kevin.Grittner@wicourts.gov>,
	pgsql-performance@postgresql.org
Subject: Re: IDE x SAS RAID 0 on HP DL 380 G5 P400i controller
	performance problem
References: <AANLkTimtyqefnmOF6xEihmoSjD333yGuYXRQ4PyVXe6j@mail.gmail.com>
	<4C440C93020000250003388D@gw.wicourts.gov>
	<AANLkTimWDBM4eOCO1mw9aR3dv4vUn58OCB-hbezn9zTZ@mail.gmail.com>
In-Reply-To: <AANLkTimWDBM4eOCO1mw9aR3dv4vUn58OCB-hbezn9zTZ@mail.gmail.com>
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Daniel Ferreira de Lima wrote:
>
>  
>
>     > **Both with Linux Kernel 2 .4.37.9 and Postgresql 7.2**
>
>     Wow.  You really need to upgrade.
>
>
> Yes, but unfortunately, actually it's impossible and economically 
> inviable...

Generally, getting good performance out of PostgreSQL 7.2 is also 
impossible and economically inviable.  You can either put resources 
toward upgrading to a newer version, which will fix many of the 
performance issues here, or toward changes to the old version that are 
not guaranteed to actually improve anything.

That said, a look into the write-caching+BBU policy on your controller 
is worthwhile.  If you're running this application successfully on some 
hardware but not others, that could be a source for the difference.

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