From: Bruce Momjian <pgman@candle.pha.pa.us>
Message-Id: <200605112345.k4BNjsP16655@candle.pha.pa.us>
Subject: Re: [PERFORM] Arguments Pro/Contra Software Raid
In-Reply-To: <20060511234124.GC4268@pervasive.com>
To: "Jim C. Nasby" <jnasby@pervasive.com>
Date: Thu, 11 May 2006 19:45:54 -0400 (EDT)
CC: "Joshua D. Drake" <jd@commandprompt.com>, Vivek Khera <vivek@khera.org>,
	"Pgsql-Performance ((E-mail))" <pgsql-performance@postgresql.org>,
	PostgreSQL General <pgsql-general@postgresql.org>
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Jim C. Nasby wrote:
> On Thu, May 11, 2006 at 07:20:27PM -0400, Bruce Momjian wrote:
> > Joshua D. Drake wrote:
> > > 
> > > >> You want an in-depth comparison of how a server disk drive is internally
> > > >> better than a desktop drive:
> > > >>
> > > >> 	http://www.seagate.com/content/docs/pdf/whitepaper/D2c_More_than_Interface_ATA_vs_SCSI_042003.pdf
> > > > 
> > > > BTW, someone (Western Digital?) is now offering SATA drives that carry
> > > > the same MTBF/warranty/what-not as their SCSI drives. I can't remember
> > > > if they actually claim that it's the same mechanisms just with a
> > > > different controller on the drive...
> > > 
> > > Well western digital and Seagate both carry 5 year warranties. Seagate I 
> > > believe does on almost all of there products. WD you have to pick the 
> > > right drive.
> > 
> > That's nice, but it seems similar to my Toshiba laptop drive experience
> > --- it breaks, we replace it.  I would rather not have to replace it.  :-)
> > 
> > Let me mention the only drive that has ever failed without warning was a
> > SCSI Deskstar (deathstar) drive, which was a hybrid because it was a
> > SCSI drive, but made for consumer use.
> 
> My damn powerbook drive recently failed with very little warning, other
> than I did notice that disk activity seemed to be getting a bit slower.
> IIRC it didn't log any errors or anything. Even if it did, if the OS was
> catching them I'd hope it would pop up a warning or something. But from
> what I've heard, some drives now-a-days will silently remap dead sectors
> without telling the OS anything, which is great until you've used up all
> of the spare sectors and there's nowhere to remap to. :(

Yes, I think most IDE drives do silently remap, and most SCSI drives
don't.  Not sure how much _most_ is.

I know my SCSI controller beeps at me when I try to access a bad block. 
Now, that gets my attention.

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

  + If your life is a hard drive, Christ can be your backup. +