Sorry, the filefrag -b option was not used correctly. Here are the new output:
https://gist.github.com/junhe/b6ce39eeb6de8887e66a#file-btrfs-debug-tree-out
https://gist.github.com/junhe/b6ce39eeb6de8887e66a#file-filefrag-out
After doing fstrim /mnt/fsonloop
https://gist.github.com/junhe/b6ce39eeb6
Thanks for the info. In the attached reproducer, I don't do sync after running
the workload (but I've tried that before.). Just to be sure, I ran again with
sync and waited for 60 seconds before collecting data. The behavior was the
same.
Then I tried one more thing, which corrected btrfs behavio
jun@jun-VirtualBox:~/workdir/b6ce39eeb6de8887e66a$ uname -r
4.2.0-rc5-integration-4.3+
https://gist.githubusercontent.com/junhe/b6ce39eeb6de8887e66a/raw/1cd84e6bb138eeb08dc07af2c44dedf99866bde0/btrfs-debug-tree.out
https://gist.githubusercontent.com/junhe/b6ce39eeb6de8887e66a/raw/1cd84e6bb138eeb0
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On 8/26/15 12:04 AM, Jun He wrote:
> Hi, I have been playing with btrfs discard for a while and found
> that btrfs may fail to discard some extents with 'mount -o
> discard'. I am aware of Jeff Mahoney's patches (
> https://patchwork.kernel.org/patch/6
Jun He posted on Tue, 25 Aug 2015 23:04:42 -0500 as excerpted:
> I have been playing with btrfs discard for a while and found that btrfs
> may fail to discard some extents with 'mount -o discard'. I am aware of
> Jeff Mahoney's patches ( https://patchwork.kernel.org/patch/6609491/ ).
> It seems th
