Re: [Qemu-devel] [PATCH v2 0/6] qcow2: cache flush fixes and performance improvements

[Kevin Wolf]

Am 04.03.2013 um 15:02 hat Stefan Hajnoczi geschrieben:
> Users have reported that qcow2 internal snapshot creation is slow.  I filed a
> bug report at https://bugs.launchpad.net/qemu/+bug/1126369.
> 
> This patch series reduces the time for qcow2 internal snapshot creation
> significantly, from more than 3 minutes to under 1 second.
> 
> In the process of removing unnecessary cache flushes, I also stumbled upon
> instances of bdrv_flush(bs->file) where we really want to flush metadata
> updates.  Since qcow2 caches metadata this actually does not write out the
> metadata updates to disk!  The fix is either bdrv_flush(bs) or a more specific
> cache flush (e.g. refcount block cache).
> 
> This series passes qemu-iotests.

Thanks, applied all to the block branch.

Kevin