On 27/08/2019 22:42, John Snow wrote: > > > On 8/23/19 11:27 AM, Vladimir Sementsov-Ogievskiy wrote: >> 16.08.2019 4:01, John Snow wrote: >>> >>> >>> On 7/19/19 12:30 PM, Andrey Shinkevich wrote: >>>> To synchronize the time when QEMU is running longer under the Valgrind, >>>> increase the sleeping time in the test 247. >>>> >>>> Signed-off-by: Andrey Shinkevich <andrey.shinkev...@virtuozzo.com> >>>> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> >>>> --- >>>> tests/qemu-iotests/247 | 6 +++++- >>>> 1 file changed, 5 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/tests/qemu-iotests/247 b/tests/qemu-iotests/247 >>>> index 546a794..c853b73 100755 >>>> --- a/tests/qemu-iotests/247 >>>> +++ b/tests/qemu-iotests/247 >>>> @@ -57,7 +57,11 @@ TEST_IMG="$TEST_IMG.4" _make_test_img $size >>>> {"execute":"block-commit", >>>> "arguments":{"device":"format-4", "top-node": "format-2", >>>> "base-node":"format-0", "job-id":"job0"}} >>>> EOF >>>> -sleep 1 >>>> +if [ "${VALGRIND_QEMU}" == "y" ]; then >>>> + sleep 10 >>>> +else >>>> + sleep 1 >>>> +fi >>>> echo '{"execute":"quit"}' >>>> ) | $QEMU -qmp stdio -nographic -nodefaults \ >>>> -blockdev >>>> file,node-name=file-0,filename=$TEST_IMG.0,auto-read-only=on \ >>>> >>> >>> This makes me nervous, though. Won't this race terribly? (Wait, why >>> doesn't it race already?) >>> >> >> Hmm, however it works somehow. I'm afraid that everything with "sleep" is >> definitely racy.. >> Or what do you mean? >> > > Right -- anything with a sleep is already at risk for racing. > > What I am picking up on here is that with valgrind, there is an even > greater computational overhead that's much harder to predict, so I was > wondering how these values were determined. >
I just followed the trend and extended the sleeping time with a grater tolerance so that the test could pass on systems where the 'sleep 1' command helps to pass without Valgrind. We could rewrite the test 247 in Python in a separate series, shall we? Andrey > (I wouldn't withhold an RB for that alone -- the sleeps are existing > problems.) > > What I moved on to wondering in particular is why test 247 doesn't > already have race problems, because it looks quite fragile. > > Neither of these are really Andrey's problems; I was just surprised > momentarily that I don't see 247 fail more often already, as-is. > > --js > -- With the best regards, Andrey Shinkevich