On Mon 14 Jan 2019 12:18:30 PM CET, Anton Nefedov wrote: > If COW areas of the newly allocated clusters are zeroes on the backing image, > efficient bdrv_write_zeroes(flags=BDRV_REQ_ALLOCATE) can be used on the whole > cluster instead of writing explicit zero buffers later in perform_cow(). > > iotest 060: > write to the discarded cluster does not trigger COW anymore. > Use a backing image instead. > > Signed-off-by: Anton Nefedov <anton.nefe...@virtuozzo.com> > Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Reviewed-by: Alberto Garcia <be...@igalia.com> > + ret = handle_alloc_space(bs, l2meta); I insist that it would be nice to have a short comment explaining what this does. Berto
