From: Amir Goldstein <amir73il@gmail.com>
Subject: Re: CrashMonkey: A Framework to Systematically Test File-System Crash Consistency
Date: Tue, 15 Aug 2017 19:13:29 +0200
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Cc: Ext4 <linux-ext4@vger.kernel.org>,
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        linux-btrfs@vger.kernel.og, vijay@cs.utexas.edu,
        Ashlie Martinez <ashmrtn@utexas.edu>,
        Josef Bacik <jbacik@fb.com>, Christoph Hellwig <hch@lst.de>
To: Vijay Chidambaram <vvijay03@gmail.com>
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On Mon, Aug 14, 2017 at 6:32 PM, Vijay Chidambaram <vvijay03@gmail.com> wrote:
> Hi,
>
> I'm Vijay Chidambaram, an Assistant Professor at the University of
> Texas at Austin. My research group is developing CrashMonkey, a
> file-system agnostic framework to test file-system crash consistency
> on power failures. We are developing CrashMonkey publicly at Github
> [1]. This is very much a work-in-progress, so we welcome feedback.
>
> CrashMonkey works by recording all the IO from running a given
> workload, then *constructing* possible crash states (while honoring
> FUA and FLUSH flags). A crash state is the state of storage after an
> abrupt power failure or crash. For each crash state, CrashMonkey runs
> the filesystem-provided fsck on top of the state, and checks if the
> file-system recovers correctly. Once the file system mounts correctly,
> we can run further tests to check data consistency.  The work was
> presented at HotStorage 17. The workshop paper is available at [2] and
> the slides at [3].
>
> Our plan was to post on the mailing lists after reproducing an
> existing bug. We are not there yet, but I saw some posts where others
> were considering building something similar, so I thought I would post
> about our work.
>
> [1] https://github.com/utsaslab/crashmonkey
> [2] http://www.cs.utexas.edu/~vijay/papers/hotstorage17-crashmonkey.pdf
> [3] http://www.cs.utexas.edu/~vijay/papers/hotstorage17-crashmonkey-slides.pdf
>

Hi Vijay,

Thanks a lot for sharing your work.
Crash consistency is high on my TODO list.

Did you happen to run into this work by Joseph Bacik?

https://www.redhat.com/archives/dm-devel/2014-November/msg00083.html

I wonder if the disk_wrapper driver could be made into something more standard
like the suggested dm-power-fail target, so that it may be proposed
for upstream?

Thanks,
Amir.