From: Marc MERLIN <marc@merlins.org>
To: Hugo Mills <hugo@carfax.org.uk>, linux-btrfs@vger.kernel.org
Subject: Re: Any use for mkfs.btrfs -d raid5 -m raid1 ?
Date: Sun, 23 Mar 2014 16:11:56 -0700 [thread overview]
Message-ID: <20140323231156.GD18293@merlins.org> (raw)
In-Reply-To: <20140323225229.GJ25400@carfax.org.uk>
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On Sun, Mar 23, 2014 at 10:52:29PM +0000, Hugo Mills wrote:
> On Sun, Mar 23, 2014 at 03:44:35PM -0700, Marc MERLIN wrote:
> > If I lose 2 drives on a raid5, -m raid1 should ensure I haven't lost my
> > metadate.
> > From there, would I indeed have small files that would be stored entirely on
> > some of the drives that didn't go missing, and therefore I could recover
> > some data with 2 missing drives?
>
> btrfs's RAID-1 is two copies only, so you may well have lost some
> of your metadata. n-copies RAID-1 is coming Real Soon Now™ (Chris has
> it on his todo list, along with fixing all the parity RAID stuff).
Oh, right, I forgot about that. Then I'm not coming up with many good
reasons why raid1 metadata with raid5 data would be useful.
Actually raid5 metadata should be faster since it's striped on more drives.
I'll update the doc I just posted, thanks.
Marc
--
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems ....
.... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/
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next prev parent reply other threads:[~2014-03-23 23:11 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-23 22:44 Any use for mkfs.btrfs -d raid5 -m raid1 ? Marc MERLIN
2014-03-23 22:52 ` Hugo Mills
2014-03-23 23:11 ` Marc MERLIN [this message]
2014-03-24 4:50 ` Benjamin O'Connor
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