From: Bruce Momjian <pgman@candle.pha.pa.us>
Message-Id: <200605101401.k4AE1XQ08859@candle.pha.pa.us>
Subject: Re: [PERFORM] Arguments Pro/Contra Software Raid
In-Reply-To: <4461F0A3.60102@logix-tt.com>
To: Markus Schaber <schabi@logix-tt.com>
Date: Wed, 10 May 2006 10:01:33 -0400 (EDT)
CC: PostgreSQL General <pgsql-general@postgresql.org>,
	"Pgsql-Performance ((E-mail))" <pgsql-performance@postgresql.org>
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Markus Schaber wrote:
> Hi, Scott & all,
> 
> Scott Lamb wrote:
> 
> > I don't know the answer to this question, but have you seen this tool?
> > 
> >     http://brad.livejournal.com/2116715.html
> 
> We had a simpler tool inhouse, which wrote a file byte-for-byte, and
> called fsync() after every byte.
> 
> If the number of fsyncs/min is higher than your rotations per minute
> value of your disks, they must be lying.
> 
> It does not find as much liers as the script above, but it is less

Why does it find fewer liers?

---------------------------------------------------------------------------

> intrusive (can be ran on every low-io machine without crashing it), and
> it found some liers in-house (some notebook disks, one external
> USB/FireWire to IDE case, and an older linux cryptoloop implementations,
> IIRC).
> 
> If you're interested, I can dig for the C source...
> 
> HTH,
> Markus
> 
> 
> 
> 
> -- 
> Markus Schaber | Logical Tracking&Tracing International AG
> Dipl. Inf.     | Software Development GIS
> 
> Fight against software patents in EU! www.ffii.org www.nosoftwarepatents.org
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 6: explain analyze is your friend
> 

-- 
  Bruce Momjian   http://candle.pha.pa.us
  EnterpriseDB    http://www.enterprisedb.com

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