From: keld@keldix.com
To: NeilBrown <neilb@suse.de>
Cc: Miles Fidelman <mfidelman@meetinghouse.net>, linux-raid@vger.kernel.org
Subject: Re: possibly silly question (raid failover)
Date: Wed, 2 Nov 2011 02:37:56 +0100 [thread overview]
Message-ID: <20111102013756.GA10763@www5.open-std.org> (raw)
In-Reply-To: <20111102092526.50b410b1@notabene.brown>
On Wed, Nov 02, 2011 at 09:25:26AM +1100, NeilBrown wrote:
> On Tue, 1 Nov 2011 23:15:39 +0100 keld@keldix.com wrote:
>
> > On Tue, Nov 01, 2011 at 04:13:26PM -0400, Miles Fidelman wrote:
> > > David Brown wrote:
> > > >
> > > >No, md RAID10 does /not/ offer more redundancy than RAID1. You are
> > > >right that md RAID10 offers more than RAID1 (or traditional RAID0 over
> > > >RAID1 sets) - but it is a convenience and performance benefit, not a
> > > >redundancy benefit. In particular, it lets you build RAID10 from any
> > > >number of disks, not just two. And it lets you stripe over all disks,
> > > >improving performance for some loads (though not /all/ loads - if you
> > > >have lots of concurrent small reads, you may be faster using plain
> > > >RAID1).
> >
> > In fact raid10 mas a bit less redundancy than raid1+0.
> > It is as far as I know built as raid0+1 with a disk layout
> > where you can only loose eg 1 out of 4 disks, while raid1+0
> > in some cases can loose 2 disks out of 4.
>
> With md/raid10 you can in some case lose 2 out of 4 disks and survive, just
> like raid1+0.
OK, in which cases, and when is this not the case?
best regards
keld
next prev parent reply other threads:[~2011-11-02 1:37 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-11-01 0:38 possibly silly question (raid failover) Miles Fidelman
2011-11-01 9:14 ` David Brown
2011-11-01 13:05 ` Miles Fidelman
2011-11-01 13:37 ` John Robinson
2011-11-01 14:36 ` David Brown
2011-11-01 20:13 ` Miles Fidelman
2011-11-01 21:20 ` Robin Hill
2011-11-01 21:32 ` Miles Fidelman
2011-11-01 21:50 ` Robin Hill
2011-11-01 22:35 ` Miles Fidelman
2011-11-01 22:00 ` David Brown
2011-11-01 22:58 ` Miles Fidelman
2011-11-02 10:36 ` David Brown
2011-11-01 22:15 ` keld
2011-11-01 22:25 ` NeilBrown
2011-11-01 22:38 ` Miles Fidelman
2011-11-02 1:40 ` keld
2011-11-02 1:37 ` keld [this message]
2011-11-02 1:48 ` NeilBrown
2011-11-02 7:02 ` keld
2011-11-02 9:20 ` Jonathan Tripathy
2011-11-02 11:27 ` David Brown
2011-11-01 9:26 ` Johannes Truschnigg
2011-11-01 13:02 ` Miles Fidelman
2011-11-01 13:33 ` John Robinson
2011-11-02 6:41 ` Stan Hoeppner
2011-11-02 13:17 ` Miles Fidelman
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