Le jeudi 04 juillet 2013 à 18:26 +0100, Graham Anderson a écrit :
On Thursday 04 Jul 2013 11:54:05 Jeff Mahoney wrote:
So, I'd like to hear your stories. What's worked for you? What hasn't worked? What would you consider the pain points with using btrfs?
When I tested a variety of KVM image formats and settings to see what worked well with regards to disk read/write speed; I found that any disk image stored on a btrfs volume made writing to the the VM filesystem (ext4) too slow to be usable for any kind of real work load.
I didn't test using btrfs volumes inside the VM's themselves.
I'm running btrfs on such setup and the way to get decent performance
(either when using only btrfs on host on in both host and guest) is to
disable CoW on the VM images, using "chattr -C". I'm wondering if we
shouldn't do that by default in qemu-img and libvirt..
--
Frederic Crozat