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Date: Mon, 20 Aug 2007 20:33:26 -0400 (EDT)
From: "Stuart D. Gathman" <stuart@bmsi.com>
Subject: Re: [linux-lvm] Flexible storga: LVM setup on top of mdadm sets.
	Good idea or not?
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To: LVM general discussion and development <linux-lvm@redhat.com>

On Mon, 23 Jul 2007, Luca Berra wrote:

> On Sun, Jul 22, 2007 at 02:57:33PM -0400, Stuart D. Gathman wrote:
> >The main drawback to md raid1 is that it always resynchronizes
> >the *entire* partition when a disk goes offline temporarily.  I also

> False. md uses bitmaps to avoid this.

Ok, I just tested this with Centos-5.0, kernel-2.6.18-8.1.8.el5.
I shutdown with md1 50% resynced, and when it boots, it starts over
at the beginning.  Maybe we are talking about different things, but
it is a major annoyance that it restarts the sync from the beginning
if it misses just one update (e.g. unexpected power failure or reboot).

-- 
	      Stuart D. Gathman <stuart@bmsi.com>
    Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flammis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.