On Sun, Sep 11, 2011 at 8:14 PM, Sage Weil <sage@xxxxxxxxxxxx> wrote: > On Fri, 9 Sep 2011, Kevin Wolf wrote: >> Am 08.09.2011 18:36, schrieb Sage Weil: >> > On Thu, 8 Sep 2011, Kevin Wolf wrote: >> >> Am 08.09.2011 01:06, schrieb Yehuda Sadeh: >> >>> The following set of patches improve the qemu-img conversion process >> >>> performance. When using a higher latency backend, small writes have a >> >>> severe impact on the time it takes to do image conversion. >> >>> We switch to using async writes, and we avoid splitting writes due to >> >>> holes when the holes are small enough. >> >>> >> >>> Yehuda Sadeh (2): >> >>> qemu-img: async write to block device when converting image >> >>> qemu-img: don't skip writing small holes >> >>> >> >>> qemu-img.c | 34 +++++++++++++++++++++++++++------- >> >>> 1 files changed, 27 insertions(+), 7 deletions(-) >> >>> >> >> >> >> This doesn't seem to be against git master or the block tree. Please rebase. >> >> >> >> I think that commit a22f123c may obsolete your patch 2/2. >> > >> > With git.kernel.org down, where should I be looking for the latest >> > upstream? >> >> qemu has never been on kernel.org. The interesting repositories for you are: >> >> * Upstream: git://git.qemu.org/qemu.git master >> * Block development branch: git://repo.or.cz/qemu/kevin.git block > > Oh right. I've been working from qemu-kvm.git. > > I've done some (still minimal) testing, and it looks like the combination > of a22f123c and the new writeback/flush stuff in librbd gets the same > result as doing async io explicitly from qemu-img.c. Want to take a look, > Yehuda? It still defaults to off, so you'll need to add > rbd_writeback_window=8000000 or similar to the rbd device string. > I'll take a look. I do have a rebased version for the qemu-img async patch, and I think qemu can benefit from that anyway. Yehuda -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
