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Date: Mon, 13 Dec 2004 18:35:00 -0800 (PST)
From: Doug White <dwhite@gumbysoft.com>
To: Joe Rhett <jrhett@meer.net>
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cc: =?iso-8859-1?Q?S=F8ren?= Schmidt <sos@DeepCore.dk>
Subject: Re: drive failure during rebuild causes page fault
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On Mon, 13 Dec 2004, Joe Rhett wrote:

> > This is why I don't trust ATA RAID for fault tolerance -- it'll save your
> > data, but the system will tank.  Since the disk state is maintained by
> > the OS and not abstracted by a separate processor, if a disk dies in a
> > particularly bad way the system may not be able to cope.
>
> Yes, but SATA isn't limited by this problem.  It does have a processor per
> disk. (this is all SATA, if I didn't make that clear)

Actually on SATA its worse -- the disk just stops responding to everything
and hangs.  If you don't detect this condition then you go into an
infinite wait.

In any case, yes the ATA RAID code could use a massive robustness pass. So
could the core ATA code.  Patches accepted :)

-- 
Doug White                    |  FreeBSD: The Power to Serve
dwhite@gumbysoft.com          |  www.FreeBSD.org