On Tue, Aug 24, 2021 at 01:15:17PM +0300, Vladimir Sementsov-Ogievskiy wrote: > There is no conflict and no dependency if we have parallel writes to > different subclusters of one cluster when the cluster itself is already > allocated. So, relax extra dependency. > ... > So small writes are more independent now and that helps to keep deeper > io queue which improves performance. > > 271 iotest output becomes racy for three allocation in one cluster. > Second and third writes may finish in different order. Second and > third requests don't depend on each other any more. Still they both > depend on first request anyway. Filter out second and third write > offsets to cover both possible outputs. > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> > --- > block/qcow2-cluster.c | 11 +++++++++++ > tests/qemu-iotests/271 | 5 ++++- > tests/qemu-iotests/271.out | 4 ++-- > 3 files changed, 17 insertions(+), 3 deletions(-) >
> +++ b/tests/qemu-iotests/271 > @@ -893,7 +893,10 @@ EOF > } > > _make_test_img -o extended_l2=on 1M > -_concurrent_io | $QEMU_IO | _filter_qemu_io > +# Second an third writes in _concurrent_io() are independent and may finish > in and > +# different order. So, filter offset out to match both possible variants. > +_concurrent_io | $QEMU_IO | _filter_qemu_io | \ > + $SED -e 's/\(20480\|40960\)/OFFSET/' > _concurrent_verify | $QEMU_IO | _filter_qemu_io > Reviewed-by: Eric Blake <ebl...@redhat.com> -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3266 Virtualization: qemu.org | libvirt.org
