From mboxrd@z Thu Jan  1 00:00:00 1970
From: Goswin von Brederlow <goswin-v-b@web.de>
Subject: Re: Poor write performance with write-intent bitmap?
Date: Wed, 22 Apr 2009 11:16:16 +0200
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In-Reply-To: <49ED2BC3.7050109@anonymous.org.uk> (John Robinson's message of
	"Tue, 21 Apr 2009 03:13:23 +0100")
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To: John Robinson <john.robinson@anonymous.org.uk>
Cc: NeilBrown <neilb@suse.de>, Linux RAID <linux-raid@vger.kernel.org>
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John Robinson <john.robinson@anonymous.org.uk> writes:

> Can't do that, my root filesystem is on the RAID-5, and part of the
> reason for wanting the bitmap is because the md can't be stopped while
> shutting down, so it was always wanting to resync at startup, which is
> rather tedious.

Normal shutdown should put the raid in read-only mode as last step. At
least Debian does that. That way even a mounted raid will be clean
after reboot.

I would also suggest restructuring your system like this:

sdX1 1GB  raid1  / (+/boot)
sdX2 rest raid5  lvm with /usr, /var, /home, ...

Both / and /usr can usualy be read-only preventing any filesystem
corruption and raid resyncs in that part of the raid.

MfG
        Goswin