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From: Miles Fidelman <mfidelman@meetinghouse.net>
Cc: linux-raid@vger.kernel.org
Subject: Re: possibly silly question (raid failover)
Date: Tue, 01 Nov 2011 16:13:26 -0400	[thread overview]
Message-ID: <4EB052E6.4050400@meetinghouse.net> (raw)
In-Reply-To: <j8p0g3$9r4$1@dough.gmane.org>

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).

wasn't suggesting that it does - just that it does things differently 
than normal raid 1+0 - for example, by doing mirroring and striping as a 
unitary operation, it works across odd number of drives - it also (I 
think) allows for more than 2 copies of a block (not completely clear 
how many copies of a block would be made if you specified a 16 drive 
array) - sort of what I'm wondering here





-- 
In theory, there is no difference between theory and practice.
In<fnord>  practice, there is.   .... Yogi Berra



  reply	other threads:[~2011-11-01 20:13 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 [this message]
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
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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