From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Fri, 29 Feb 2008 18:31:48 +0000
From: Alasdair G Kergon <agk@redhat.com>
Subject: Re: [linux-lvm] Page cache corruption when creating a snapshot
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References: <200802291732.m1THWfD7013248@outgoing.mit.edu>
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To: ghudson@MIT.EDU
Cc: linux-lvm@redhat.com

On Fri, Feb 29, 2008 at 12:32:41PM -0500, ghudson@MIT.EDU wrote:
> The reproduction recipe looks like:
>   rm -rf /tmp/test
>   mkdir /tmp/test
>   # Put around 60MB of files into /tmp/test
>   find /tmp/test -type f | xargs md5sum > /tmp/sum.pre
>   lvcreate --size 2G --snapshot /dev/dink/gutsy-i386-sbuild --name testsnapshot
>   find /tmp/test -type f | xargs md5sum > /tmp/sum.post

Can you do that twice?
    find /tmp/test -type f | xargs md5sum > /tmp/sum.post2
and check the two post files are the same?

And add some syncs/blockdev --flushbufs at different places
in the script to see if you can make it go away.

Alasdair
-- 
agk@redhat.com