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From: "H. Peter Anvin" <hpa@zytor.com>
To: linux-btrfs <linux-btrfs@vger.kernel.org>
Subject: Feature request: true RAID-1 mode
Date: Wed, 20 Jun 2012 09:27:16 -0700	[thread overview]
Message-ID: <4FE1F9E4.5090301@zytor.com> (raw)

Yet another boot loader support request.

Right now btrfs' definition of "RAID-1" with more than two devices is a
bit unorthodox: it stores on any two drives.  "True RAID-1" would
instead store N copies on each of N devices, the same way an actual
RAID-1 would operate with an arbitrary number of devices.

This means that a bootloader can consider a single device in isolation:
if the firmware gives access only to a single device, it can be booted.
 Since /boot is usually a very small amount of data, this is a very
reasonable tradeoff.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.


             reply	other threads:[~2012-06-20 16:27 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-06-20 16:27 H. Peter Anvin [this message]
2012-06-21  0:35 ` Feature request: true RAID-1 mode Marios Titas
2012-06-21  0:50   ` Chris Mason
2012-06-21  1:34     ` H. Peter Anvin
2012-06-25 15:21       ` Chris Mason
2012-06-25 17:46         ` H. Peter Anvin
2012-06-25 22:34           ` Gareth Pye
     [not found]           ` <CA+WRLO87LvTrRJRMNwYQ3SwmZWF7WzO_FDi1=jqt1kwX=YSnWQ@mail.gmail.com>
2012-06-25 22:37             ` H. Peter Anvin
2012-06-25 22:46               ` Gareth Pye
2012-06-25 22:54           ` Hugo Mills
2012-06-25 23:00             ` H. Peter Anvin
2012-07-02 15:59               ` H. Peter Anvin

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