From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bart Van Assche <bvanassche@acm.org>
Subject: Re: [PATCH RFC 00/10] dm-dedup: device-mapper
 deduplication target
Date: Tue, 29 Apr 2014 08:23:39 +0200
Message-ID: <535F456B.5090600@acm.org>
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Cc: Christoph Hellwig <hch@infradead.org>, Philip Shilane <philip.shilane@emc.com>, Sonam Mandal <sonam.dp42@gmail.com>, Erez Zadok <ezk@fsl.cs.sunysb.edu>
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On 04/29/14 00:03, Vasily Tarasov wrote:
> See the documentation patch for more details.

Regarding that documentation: shouldn't the on-disk data structures be
documented ? Shouldn't it be documented how dm-dedup recovers from a
power failure ? Since different storage devices are used for data and
meta-data recovery from a power failure is nontrivial. How is it e.g.
guaranteed if a data block has been made persistent (e.g. via REQ_FUA)
and the refcount is increased for that data block that neither the data
nor the metadata for that data block is lost if a power failure occurs ?

Bart.