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Subject: Re: [PERFORM] Arguments Pro/Contra Software Raid
From: Scott Marlowe <smarlowe@g2switchworks.com>
To: Douglas McNaught <doug@mcnaught.org>
Cc: Bruce Momjian <pgman@candle.pha.pa.us>, Steve Atkins <steve@blighty.com>,
	PostgreSQL General <pgsql-general@postgresql.org>,
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On Wed, 2006-05-10 at 09:51, Douglas McNaught wrote:
> Scott Marlowe <smarlowe@g2switchworks.com> writes:
> 
> > On Tue, 2006-05-09 at 20:02, Bruce Momjian wrote:
> 
> >> You do if the controller thinks the data is already on the drives and
> >> removes it from its cache.
> >
> > Bruce, re-read what I wrote.  The escalades tell the drives to TURN OFF
> > THEIR OWN CACHE.
> 
> Some ATA drives would lie about that too IIRC.  Hopefully they've
> stopped doing it in the SATA era.

Ugh.  Now that would make for a particularly awful bit of firmware
implementation.  I'd think that if I found a SATA drive doing that I'd
be likely to strike the manufacturer off of the list for possible future
purchases...