Re: [Qemu-devel] [PATCH 1/2] qemu-iotests: Speed up make check-block

[Kevin Wolf <kwolf@redhat.com>]

Am 25.11.2014 um 10:21 hat Max Reitz geschrieben:
> On 2014-11-25 at 10:21, Kevin Wolf wrote:
> >Am 25.11.2014 um 10:12 hat Max Reitz geschrieben:
> >>On 2014-10-28 at 07:45, Fam Zheng wrote:
> >>>Using /tmp (usually mounted as tmpfs) and cache=writeback, the quick
> >>>group can be quicker.
> >>>
> >>>On my laptop (Lenovo T430s with Fedora 20), this reduces the time from
> >>>50s to 30s.
> >>>
> >>>Signed-off-by: Fam Zheng <famz@redhat.com>
> >>>---
> >>>  tests/qemu-iotests-quick.sh | 2 +-
> >>>  1 file changed, 1 insertion(+), 1 deletion(-)
> >>>
> >>>diff --git a/tests/qemu-iotests-quick.sh b/tests/qemu-iotests-quick.sh
> >>>index 12af731..0b54dbf 100755
> >>>--- a/tests/qemu-iotests-quick.sh
> >>>+++ b/tests/qemu-iotests-quick.sh
> >>>@@ -3,6 +3,6 @@
> >>>  cd tests/qemu-iotests
> >>>  ret=0
> >>>-./check -T -qcow2 -g quick || ret=1
> >>>+TEST_DIR=/tmp/qemu-iotests-quick-$$ ./check -T -qcow2 -g quick -c writeback || ret=1
> >>There are (at least) two tests which don't work with -c writeback
> >>(026 and 039), one of them is in the quick group (039). Why not use
> >>-c writethrough? It doesn't make any difference on tmpfs anyway  (we
> >>can't omit it because that will break 091).
> >Why use any -c? The default is the fast option writeback, and for those
> >test cases that don't support writeback, something working is chosen
> >instead.
> 
> Because that breaks 091.

That's unfortunate. I wish tmpfs supported O_DIRECT...

But let's just remove it from quick then - it doesn't really matter if
it doesn't run because of the cache mode or because we didn't include it
in the group.

-c writethrough is okay as long as you really have tmpfs on your /tmp,
but it really hurts when you don't (and I for one don't, standard RHEL 7
installation).

Kevin