On Mon, Jul 12, 2010 at 9:09 AM, Michael Tokarev <m...@tls.msk.ru> wrote: > > This looks quite similar to a problem with ext4 and O_SYNC which I > reported earlier but no one cared to answer (or read?) - there: > http://permalink.gmane.org/gmane.linux.file-systems/42758 > (sent to qemu-devel and linux-fsdevel lists - Cc'd too). You can > try a few other options, esp. cache=none and re-writing some guest > files to verify. > > /mjt > Either way, changing to cache=none I suspect wouldn't tell me much, because if it's as slow as before, it's still unusable and if instead it's even slower, well it'd be even more unusable, so I wouldn't be able to tell the difference. What I can say for certain is that with the exact same virtual hd file, same options, same system, but on an ext3 fs there's no problem at all, on a Btrfs is not just slower, it takes ages.
-- Giangiacomo
