From: Loic Dachary <loic@dachary.org>
To: Ceph Development <ceph-devel@vger.kernel.org>
Subject: crc32 for erasure code
Date: Mon, 23 Sep 2013 10:34:35 +0200 [thread overview]
Message-ID: <523FFD1B.4030801@dachary.org> (raw)
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Hi,
Unless I'm mistaken, ceph_crc32() is currently used in master via the crc32c() method of bufferlist to:
* encode_with_checksum/decode_with_checksum a PGLog entry
* Message::decode_message/Message::encode_message a message via calc_*_crc
* FileJournal::do_read_entry/FileJournal::prepare_single_write a journal entry
* for information in the report monitory command ( Monitor.cc )
Erasure coded chunks ( i.e. files ) will need checksums. Should this be implemented as an optional feature in ceph/src/os/FileStore.{h,cc} ? If the underlying filesystem does not provide this feature, FileStore would call ceph_crc32 each time the object is modified. A verification method would be exposed and used when scrubbing erasure coded pools.
Cheers
--
Loïc Dachary, Artisan Logiciel Libre
All that is necessary for the triumph of evil is that good people do nothing.
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next reply other threads:[~2013-09-23 8:44 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-23 8:34 Loic Dachary [this message]
2013-09-23 16:59 ` crc32 for erasure code Gregory Farnum
2013-09-23 17:10 ` Loic Dachary
2013-09-23 17:14 ` Gregory Farnum
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