Date: Tue, 5 Aug 2008 13:29:57 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: linasvepstas@gmail.com
Cc: "Robert Hancock" <hancockr@shaw.ca>, "John Stoffel" <john@stoffel.org>,
       "Alistair John Strachan" <alistair@devzero.co.uk>,
       linux-kernel@vger.kernel.org
Subject: Re: amd64 sata_nv (massive) memory corruption
Message-ID: <20080805132957.398c1036@lxorguk.ukuu.org.uk>
In-Reply-To: <3ae3aa420808042229l675ffd79p42a5691532b7ac3b@mail.gmail.com>
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> have EDAC turned on, or something ... I'm investigating now.
> But this is moot -- if there is software that already exists that
> could have reported the error to the kernel, then this software
> should have been installed/enabled/operating by default.

That gets you into arguments with the people who care about performance
but its really a distribution level debate and I suspect the answer is
itself distro specific depending on usage/

> Personally I'm ready to pop $$$ for ECC it if will actually do
> something for me, this has been painful.

On a decent system ECC will do something. A modern server PC actually has
pretty good coverage on CPU L1, L2 and optionally RAM. I/O controllers
and disk internal caches seem to be a bit more variable which is one
reason big HPC cluster projects often checksum end to end - when you
produce terabytes of data all the one in a hundred billion error stats
start to look less than reassuring.

Alan
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