Date: Wed, 4 Apr 2007 09:19:20 -0400
From: Alvaro Herrera <alvherre@commandprompt.com>
To: Andreas Kostyrka <andreas@kostyrka.org>
Cc: Peter Kovacs <maxottovonstirlitz@gmail.com>,
	"david@lang.hm" <david@lang.hm>, Geoff Tolley <geoff@polimetrix.com>,
	Ron <rjpeace@earthlink.net>, "jason@ohloh.net" <jason@ohloh.net>,
	pgsql-performance@postgresql.org
Subject: Re: SCSI vs SATA
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	Peter Kovacs <maxottovonstirlitz@gmail.com>,
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	Geoff Tolley <geoff@polimetrix.com>, Ron <rjpeace@earthlink.net>,
	"jason@ohloh.net" <jason@ohloh.net>,
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Andreas Kostyrka escribió:
> * Peter Kovacs <maxottovonstirlitz@gmail.com> [070404 14:40]:
> > This may be a silly question but: will not 3 times as many disk drives
> > mean 3 times higher probability for disk failure? Also rumor has it
> > that SATA drives are more prone to fail than SCSI drivers. More
> > failures will result, in turn, in more administration costs.
> Actually, the newest research papers show that all discs (be it
> desktops, or highend SCSI) have basically the same failure statistics.
> 
> But yes, having 3 times the discs will increase the fault probability.

... of individual disks, which is quite different from failure of a disk
array (in case there is one).

-- 
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.