Re: [PATCH 4/7] iotests/129: Use throttle node

[Vladimir Sementsov-Ogievskiy]

13.01.2021 20:02, Max Reitz wrote:
> On 13.01.21 17:46, Vladimir Sementsov-Ogievskiy wrote:
> > 13.01.2021 17:06, Max Reitz wrote:
> > > Throttling on the BB has not affected block jobs in a while, so it is
> > > possible that one of the jobs in 129 finishes before the VM is stopped.
> > > We can fix that by running the job from a throttle node.
> > >
> > > Signed-off-by: Max Reitz <mreitz@redhat.com>
> > > ---
> > >   tests/qemu-iotests/129 | 39 +++++++++++++++------------------------
> > >   1 file changed, 15 insertions(+), 24 deletions(-)
> > >
> > > diff --git a/tests/qemu-iotests/129 b/tests/qemu-iotests/129
> > > index dd23bb2e5a..febc806398 100755
> > > --- a/tests/qemu-iotests/129
> > > +++ b/tests/qemu-iotests/129
> > > @@ -32,20 +32,18 @@ class TestStopWithBlockJob(iotests.QMPTestCase):
> > >           iotests.qemu_img('create', '-f', iotests.imgfmt, self.test_img,
> > >                            "-b", self.base_img, '-F', iotests.imgfmt)
> > >           iotests.qemu_io('-f', iotests.imgfmt, '-c', 'write -P0x5d 1M 128M', 
> > > self.test_img)
> > > -        self.vm = iotests.VM().add_drive(self.test_img)
> > > +        self.vm = iotests.VM()
> > > +        self.vm.add_object('throttle-group,id=tg0,x-bps-total=1024')
> > > +
> > > +        source_drive = 'driver=throttle,' + \
> > > +                       'throttle-group=tg0,' + \
> > > +                      f'file.driver={iotests.imgfmt},' + \
> > > +                      f'file.file.filename={self.test_img}'
> >
> > python has a "c-like" string "concatenation", i.e., you may omit "+" operators 
> > (I don't know is it a good practice, but I do so:)
>
> OK, why not.
>
> > > +
> > > +        self.vm.add_drive(None, source_drive)
> > >           self.vm.launch()
> > >       def tearDown(self):
> > > -        params = {"device": "drive0",
> > > -                  "bps": 0,
> > > -                  "bps_rd": 0,
> > > -                  "bps_wr": 0,
> > > -                  "iops": 0,
> > > -                  "iops_rd": 0,
> > > -                  "iops_wr": 0,
> > > -                 }
> > > -        result = self.vm.qmp("block_set_io_throttle", conv_keys=False,
> > > -                             **params)
> > >           self.vm.shutdown()
> > >           for img in (self.test_img, self.target_img, self.base_img):
> > >               iotests.try_remove(img)
> > > @@ -53,33 +51,26 @@ class TestStopWithBlockJob(iotests.QMPTestCase):
> > >       def do_test_stop(self, cmd, **args):
> > >           """Test 'stop' while block job is running on a throttled drive.
> > >           The 'stop' command shouldn't drain the job"""
> > > -        params = {"device": "drive0",
> > > -                  "bps": 1024,
> > > -                  "bps_rd": 0,
> > > -                  "bps_wr": 0,
> > > -                  "iops": 0,
> > > -                  "iops_rd": 0,
> > > -                  "iops_wr": 0,
> > > -                 }
> > > -        result = self.vm.qmp("block_set_io_throttle", conv_keys=False,
> > > -                             **params)
> > > -        self.assert_qmp(result, 'return', {})
> > >           result = self.vm.qmp(cmd, **args)
> > >           self.assert_qmp(result, 'return', {})
> > > +
> > >           result = self.vm.qmp("stop")
> > >           self.assert_qmp(result, 'return', {})
> > >           result = self.vm.qmp("query-block-jobs")
> > > +
> > >           self.assert_qmp(result, 'return[0]/status', 'running')
> > >           self.assert_qmp(result, 'return[0]/ready', False)
> > > +        self.vm.qmp("block-job-cancel", device="drive0", force=True)
> >
> > won't hurt, but I'd drop it as unrelated to commit
> >
> > > +
> > >       def test_drive_mirror(self):
> > >           self.do_test_stop("drive-mirror", device="drive0",
> > > -                          target=self.target_img,
> > > +                          target=self.target_img, format=iotests.imgfmt,
> > >                             sync="full")
> >
> > this doesn't seem need/related too..
>
> It is, because without a @format parameter, the job uses the driver of @device 
> as the output format.  That driver is now 'throttle', which doesn’t work as a 
> format.

Ah, understand now, OK.


--
Best regards,
Vladimir