From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paul Clements <paul.clements@steeleye.com>
Subject: Re: NVRAM support
Date: Fri, 10 Feb 2006 12:38:38 -0500
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To: Mirko Benz <mirko.benz@web.de>
Cc: linux-raid@vger.kernel.org
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Mirko Benz wrote:

> Does a high speed NVRAM device makes sense for Linux SW RAID? E.g. a PCI 
> card that exports battery backed memory.

Sure. There are a couple ways I can think of using such a thing:

1) put an md intent bitmap on the NVRAM device for faster resyncs

2) use the NVRAM as a write journal for md to make md raid4/5/6 reliable 
(if the system crashes while an md raid5 is degraded, i.e., missing a 
disk, there is a chance of silent data corruption). The md driver does 
not currently do write journalling, so this would require some code changes.

--
Paul