Description of problem: I've run btrfs balance start -dconvert=raid1 -mconvert=raid1 /mnt twice now on my btrfs mount (2tb data, 2x5tb drives). It takes 10+ hours, seems to be working, but when its done nothing has changed. The btrfs mount is still data=single, metadata=DUP. This appears to be a bug in the 4.0 kernel. See here: https://patchwork.kernel.org/patch/6238111/ and here: http://article.gmane.org/gmane.comp.file-systems.btrfs/44696
Known regression. Original revert message 19.Apr http://thread.gmane.org/gmane.comp.file-systems.btrfs/44477 Chris Mason working on a tested fix 29.Apr http://thread.gmane.org/gmane.comp.file-systems.btrfs/44477 kernel-4.1.0.rc3 this is still a bug.
Bad paste Chris Mason working on tested fix: http://article.gmane.org/gmane.comp.file-systems.btrfs/44801
https://git.kernel.org/cgit/linux/kernel/git/mason/linux-btrfs.git/commit/?h=for-linus-4.1&id=153c35b6cccc0c72de9fae06c8e2c8b2c47d79d4
A bunch of patches finally got submitted for 4.0.y stable today. I'll look at bringing them in.
Patches applied. They'll be in the next build.
Niiice. Thanks Josh!
It looks like this was finally fixed upstream, in 4.0.6: https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.0.6
kernel-4.0.6-300.fc22 has been submitted as an update for Fedora 22. https://admin.fedoraproject.org/updates/kernel-4.0.6-300.fc22
kernel-4.0.6-200.fc21 has been submitted as an update for Fedora 21. https://admin.fedoraproject.org/updates/kernel-4.0.6-200.fc21
Package kernel-4.0.6-300.fc22: * should fix your issue, * was pushed to the Fedora 22 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing kernel-4.0.6-300.fc22' as soon as you are able to, then reboot. Please go to the following url: https://admin.fedoraproject.org/updates/FEDORA-2015-10677/kernel-4.0.6-300.fc22 then log in and leave karma (feedback).
I created a btrfs volume using two loopback devices and I was able to balance the volume to raid1 successfully using kernel-4.0.6-300. I've added positive karma to the package. Thanks everyone!
kernel-4.0.6-300.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.
kernel-4.0.6-200.fc21 has been pushed to the Fedora 21 stable repository. If problems still persist, please make note of it in this bug report.