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

[Kevin Wolf]

Am 25.11.2014 um 10:44 hat Fam Zheng geschrieben:
> On Tue, 11/25 10:31, Max Reitz wrote:
> > On 2014-11-25 at 10:30, Kevin Wolf wrote:
> > >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 <address@hidden>
> > >>>>>---
> > >>>>>  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...
> 
> Indeed unfortunate!
> 
> > >
> > >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.
> 
> Will do it when respin.
> 
> > >-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).
> > 
> 
> Oh, do you have any better idea than hardcoding to /tmp then?

I think /tmp is fine. It helps those of us who do have a tmpfs there,
and it shouldn't hurt the rest at least. Just don't combine it with
writethrough, but leave out -c.

Kevin