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From: "Darrick J. Wong" <darrick.wong@oracle.com>
To: "Theodore Ts'o" <tytso@mit.edu>
Cc: linux-ext4@vger.kernel.org, dm-devel@redhat.com
Subject: Re: Some thoughts about providing data block checksumming for ext4
Date: Wed, 26 Nov 2014 15:47:06 -0800	[thread overview]
Message-ID: <20141126234706.GN10043@birch.djwong.org> (raw)
In-Reply-To: <20141103233308.GA27842@thunk.org>

Sigh...

Well, I wrote up a preliminary version of dm-checksum and then
realized that I've pretty much just built a crappier version of
dm-dedupe, but without the dedupe part.  Given that it stores
checksums in a btree which claims to be robust through failures and
gives us automatic deduplication, I wonder if it we could achieve our
aims by modifying dm-dedupe to verify the checksums on the read path?

I guess it would be interesting to see how bad the performance hit is
with the online dedupe part enabled or disabled.  dm-dedupe v2 went
out on the mailing list last August, which I missed. :(

Unless... there's a specific reason nobody mentioned dm-dedupe here?

--D

  parent reply	other threads:[~2014-11-26 23:47 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-11-03 23:33 Some thoughts about providing data block checksumming for ext4 Theodore Ts'o
2014-11-04 21:20 ` Andreas Dilger
2014-11-04 23:58   ` Theodore Ts'o
2014-11-04 21:39 ` [dm-devel] " Mikulas Patocka
2014-11-04 22:06   ` Mikulas Patocka
2014-11-05  0:27     ` Mikulas Patocka
2014-11-05 21:37       ` Milan Broz
2014-11-06 12:55         ` Theodore Ts'o
2014-11-05  2:33   ` Theodore Ts'o
2014-11-26 23:47 ` Darrick J. Wong [this message]
2014-11-27  0:07   ` Mike Snitzer
2014-11-27  0:39     ` Darrick J. Wong
2015-01-23 16:46       ` [dm-devel] " Vasily Tarasov

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