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From: Chris Murphy <lists@colorremedies.com>
Date: Sat, 23 Jul 2016 14:05:01 -0600
Message-ID: <CAJCQCtQYicoze=jBf9ptQABLZSxgd67MYUbCs2igB2PipugxaA@mail.gmail.com>
Subject: Re: qcow2 becomes 37P in size while qemu crashes
To: Chris Murphy <lists@colorremedies.com>
Cc: Btrfs BTRFS <linux-btrfs@vger.kernel.org>
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Using btrfs-debug-tree, I'm finding something a bit odd about some of
the items in this 39P file.

Seems normal

    item 71 key (994163 EXTENT_DATA 43689967616) itemoff 12467 itemsize 53
        extent data disk byte 617349906432 nr 80805888
        extent data offset 0 nr 80805888 ram 80805888
        extent compression(none)

Seems not normal

    item 58 key (994163 EXTENT_DATA 38345535488) itemoff 13156 itemsize 53
        extent data disk byte 0 nr 0
        extent data offset 394752000 nr 61440 ram 34626881742770176
        extent compression(none)

There are quite a large number of items that take the 2nd form, and in
each case the ram value is the same as above.


-- 
Chris Murphy