On Tue, Jun 09, 2020 at 06:00:17PM +0100, Dr. David Alan Gilbert wrote: > * Michael S. Tsirkin (m...@redhat.com) wrote: > > On Wed, Mar 25, 2020 at 01:16:26PM +0000, Dr. David Alan Gilbert (git) > > wrote: > > > From: Philippe Mathieu-Daudé <phi...@redhat.com> > > > > > > When using max-bandwidth=~100Mb/s, this test fails on Travis-CI > > > s390x when configured with --disable-tcg: > > > > > > $ make check-qtest > > > TEST check-qtest-s390x: tests/qtest/boot-serial-test > > > qemu-system-s390x: -accel tcg: invalid accelerator tcg > > > qemu-system-s390x: falling back to KVM > > > TEST check-qtest-s390x: tests/qtest/pxe-test > > > TEST check-qtest-s390x: tests/qtest/test-netfilter > > > TEST check-qtest-s390x: tests/qtest/test-filter-mirror > > > TEST check-qtest-s390x: tests/qtest/test-filter-redirector > > > TEST check-qtest-s390x: tests/qtest/drive_del-test > > > TEST check-qtest-s390x: tests/qtest/device-plug-test > > > TEST check-qtest-s390x: tests/qtest/virtio-ccw-test > > > TEST check-qtest-s390x: tests/qtest/cpu-plug-test > > > TEST check-qtest-s390x: tests/qtest/migration-test > > > ** > > > ERROR:tests/qtest/migration-test.c:1229:test_migrate_auto_converge: > > > 'got_stop' should be FALSE > > > ERROR - Bail out! > > > ERROR:tests/qtest/migration-test.c:1229:test_migrate_auto_converge: > > > 'got_stop' should be FALSE > > > make: *** [tests/Makefile.include:633: check-qtest-s390x] Error 1 > > > > > > Per David Gilbert, "it could just be the writing is slow on s390 > > > and the migration thread fast; in which case the autocomplete > > > wouldn't be needed. Perhaps we just need to reduce the bandwidth > > > limit." > > > > > > Tuning the threshold by reducing the initial bandwidth makes the > > > autoconverge test pass. > > > > > > Suggested-by: Dr. David Alan Gilbert <dgilb...@redhat.com> > > > Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com> > > > Message-Id: <20200323184015.11565-1-phi...@redhat.com> > > > Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com> > > > Tested-by: Alex Bennée <alex.ben...@linaro.org> > > > Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com> > > > > > > This slows make check down significantly for me, it stays > > at the migration test for minutes. > > Is this on the s390x version or all of them?
x86 slows down for me. > > I'm carrying a revert at top of my tree for now but I'd rather > > not need that. > > > > > > This seems like a fragile way to test things anyway. > > What happens if someone slows writing even more > > e.g. because it's running in a container or a VM? > > > > How about detecting that migration finished too early > > and slowing it down until autocomplete triggers? > > THe problem is you can't rely on any form of consistency in a heavily > contended container, so the fact that it took n-seconds to migrate at > this attempt means very little about what the next attempt will take. > > Dave What I'm saying is try migrating quickly. If it's too quick try again ... > > > > > > > --- > > > tests/qtest/migration-test.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c > > > index 3d6cc83b88..2568c9529c 100644 > > > --- a/tests/qtest/migration-test.c > > > +++ b/tests/qtest/migration-test.c > > > @@ -1211,7 +1211,7 @@ static void test_migrate_auto_converge(void) > > > * without throttling. > > > */ > > > migrate_set_parameter_int(from, "downtime-limit", 1); > > > - migrate_set_parameter_int(from, "max-bandwidth", 100000000); /* > > > ~100Mb/s */ > > > + migrate_set_parameter_int(from, "max-bandwidth", 1000000); /* ~1Mb/s > > > */ > > > > > > /* To check remaining size after precopy */ > > > migrate_set_capability(from, "pause-before-switchover", true); > > > -- > > > 2.25.1 > > > > > > > > > -- > Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
