Re: [Qemu-block] [PATCH v4 for 2.12 0/3] fix bitmaps migration through shared storage

[Vladimir Sementsov-Ogievskiy]

27.03.2018 12:28, Vladimir Sementsov-Ogievskiy wrote:
> 26.03.2018 21:06, Max Reitz wrote:
> > On 2018-03-20 18:05, Vladimir Sementsov-Ogievskiy wrote:
> > > Hi all.
> > >
> > > This fixes bitmaps migration through shared storage. Look at 02 for
> > > details.
> > >
> > > The bug introduced in 2.10 with the whole qcow2 bitmaps feature, so
> > > qemu-stable in CC. However I doubt that someone really suffered from 
> > > this.
> > >
> > > Do we need dirty bitmaps at all in inactive case? - that was a 
> > > question in v2.
> > > And, keeping in mind that we are going to use inactive mode not only 
> > > for
> > > incoming migration, I'm not sure that answer is NO (but, it may be 
> > > "NO" for
> > > 2.10, 2.11), so let's fix it in proposed here manner at least for 2.12.
> > For some reason, I can't get 169 to work now at all[1].  What's more,
> > whenever I run it, two (on current master, maybe more after this series)
> > "cat $TEST_DIR/mig_file" processes stay around.  That doesn't seem 
> > right.
> >
> > However, this series doesn't seem to make it worse[2]...  So I'm keeping
> > it.  I suppose it's just some issue with the test.
> >
> > Max
> >
> >
> > [1] Sometimes there are migration even timeouts, sometimes just VM
> > launch timeouts (specifically when VM B is supposed to be re-launched
> > just after it has been shut down), and sometimes I get a dirty bitmap
> > hash mismatch.
> >
> >
> > [2] The whole timeline was:
> >
> > - Apply this series, everything seems alright
> >
> > (a couple of hours later)
> > - Test some other things, stumble over 169 once or so
> >
> > - Focus on 169, fails a bit more often
> >
> > (today)
> > - Can't get it to work at all
> >
> > - Can't get it to work in any version, neither before nor after this 
> > patch
> >
> > - Lose my sanity
> >
> > - Write this email
> >
> > O:-)
>
> hmm.. checked on current master (7b93d78a04aa24), tried a lot of times 
> in a loop, works for me. How can I help?

O, loop finally finished, with:

169 6s ... [failed, exit status 1] - output mismatch (see 169.out.bad)
--- /work/src/qemu/master/tests/qemu-iotests/169.out    2018-03-16 
21:01:19.536765587 +0300
+++ /work/src/qemu/master/tests/qemu-iotests/169.out.bad 2018-03-27 
12:33:03.804800350 +0300
@@ -1,5 +1,20 @@
-........
+......E.
+======================================================================
+ERROR: test__persistent__not_migbitmap__offline 
(__main__.TestDirtyBitmapMigration)
+methodcaller(name, ...) --> methodcaller object
+----------------------------------------------------------------------
+Traceback (most recent call last):
+  File "169", line 129, in do_test_migration
+    self.vm_b.event_wait("RESUME", timeout=10.0)
+  File 
"/work/src/qemu/master/tests/qemu-iotests/../../scripts/qemu.py", line 
349, in event_wait
+    event = self._qmp.pull_event(wait=timeout)
+  File 
"/work/src/qemu/master/tests/qemu-iotests/../../scripts/qmp/qmp.py", 
line 216, in pull_event
+    self.__get_events(wait)
+  File 
"/work/src/qemu/master/tests/qemu-iotests/../../scripts/qmp/qmp.py", 
line 124, in __get_events
+    raise QMPTimeoutError("Timeout waiting for event")
+QMPTimeoutError: Timeout waiting for event
+
 ----------------------------------------------------------------------
 Ran 8 tests

-OK
+FAILED (errors=1)
Failures: 169
Failed 1 of 1 tests


and I have a lot of opened pipes, like:

root       18685  0.0  0.0 107924   352 pts/0    S    12:19   0:00 cat 
/work/src/qemu/master/tests/qemu-iotests/scratch/mig_file

...

restart testing loop, it continues to pass 169 again and again...

--
Best regards,
Vladimir