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From: Peter Waller <peter@scraperwiki.com>
Date: Thu, 31 Jul 2014 16:10:52 +0100
Message-ID: <CAFChkqtVPBembgw859O3wNTv3VMGdHjoorSrtSWL30SVj3AaAw@mail.gmail.com>
Subject: Re: Machine lockup due to btrfs-transaction on AWS EC2 Ubuntu 14.04
To: linux-btrfs@vger.kernel.org
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I should add that I have reproduced this even after doing `mount -o
clear_cache /dev/... /mnt/...`, unmount, remount with `-o
space_cache`. After the machine lockup and rebooting there are the
warnings of the form:

> [ 117.288248] BTRFS warning (device dm-0): block group 694165700608 has wrong amount of free space
> [ 117.288253] BTRFS warning (device dm-0): failed to load free space cache for block group 694165700608, rebuild it now