From: Erik Mouw <erik@harddisk-recovery.com>
To: Mirko Benz <mirko.benz@web.de>
Cc: linux-raid@vger.kernel.org
Subject: Re: NVRAM support
Date: Fri, 10 Feb 2006 13:42:05 +0100 [thread overview]
Message-ID: <20060210124204.GC28676@harddisk-recovery.com> (raw)
In-Reply-To: <43EC5655.1060504@web.de>
On Fri, Feb 10, 2006 at 10:01:09AM +0100, 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.
Unless it's very large (i.e.: as large as one of your disks), it
doesn't make sense. It will probably break less often, but it doesn't
help you in case a disk really breaks. It also won't speed up an MD
device much.
> Could that significantly improve write speed for RAID 5/6 (e.g. via an
> external journal, asynchronous operation and write caching)?
You could use it for an external journal, or you could use it as a swap
device.
> What changes would be required?
None, ext3 supports external journals. Look for the -O option in the
mke2fs manual page. Using the NVRAM device as swap is not different
from a using "normal" swap partition.
Erik
--
+-- Erik Mouw -- www.harddisk-recovery.com -- +31 70 370 12 90 --
| Lab address: Delftechpark 26, 2628 XH, Delft, The Netherlands
next prev parent reply other threads:[~2006-02-10 12:42 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-02-10 9:01 NVRAM support Mirko Benz
2006-02-10 12:42 ` Erik Mouw [this message]
2006-02-10 15:43 ` Bill Davidsen
2006-02-11 1:02 ` dean gaudet
2006-02-13 9:22 ` Erik Mouw
2006-02-13 11:54 ` Andy Smith
2006-02-13 13:35 ` Guy
2006-02-14 10:17 ` Erik Mouw
2006-02-15 8:24 ` Mirko Benz
2006-02-15 23:00 ` Neil Brown
2006-02-16 10:05 ` Mario 'BitKoenig' Holbe
2006-02-20 9:57 ` Mirko Benz
2006-02-20 23:16 ` Neil Brown
2006-02-10 17:38 ` Paul Clements
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