migration test tweeks

[PATCH 0/2] migration test tweeks

Posted by Dr. David Alan Gilbert (git) 4 years, 7 months ago

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Alex noticed that some of the postcopy tests would occasionally
hang; this series adds some checks to make them more likely
to assert than hang in some failure cases, and changes
the migration bandwidth so that under load it's much more likely
to manage to land in postcopy.

Dr. David Alan Gilbert (2):
  tests/migration: Fail on unexpected migration states
  tests/migration/postcopy: trim migration bandwidth

 tests/migration-test.c | 25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

-- 
2.21.0

Re: [PATCH 0/2] migration test tweeks

Posted by Dr. David Alan Gilbert 4 years, 7 months ago

* Dr. David Alan Gilbert (git) (dgilbert@redhat.com) wrote:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> 
> Alex noticed that some of the postcopy tests would occasionally
> hang; this series adds some checks to make them more likely
> to assert than hang in some failure cases, and changes
> the migration bandwidth so that under load it's much more likely
> to manage to land in postcopy.

Queued

> 
> Dr. David Alan Gilbert (2):
>   tests/migration: Fail on unexpected migration states
>   tests/migration/postcopy: trim migration bandwidth
> 
>  tests/migration-test.c | 25 ++++++++++++++++++-------
>  1 file changed, 18 insertions(+), 7 deletions(-)
> 
> -- 
> 2.21.0
> 
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK

Re: [PATCH 0/2] migration test tweeks

Posted by Peter Xu 4 years, 7 months ago

On Mon, Sep 23, 2019 at 02:10:20PM +0100, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> 
> Alex noticed that some of the postcopy tests would occasionally
> hang; this series adds some checks to make them more likely
> to assert than hang in some failure cases, and changes
> the migration bandwidth so that under load it's much more likely
> to manage to land in postcopy.
> 
> Dr. David Alan Gilbert (2):
>   tests/migration: Fail on unexpected migration states
>   tests/migration/postcopy: trim migration bandwidth

Reviewed-by: Peter Xu <peterx@redhat.com>

I might be even more aggresive on patch 2 when turning down the
bandwidth. :)

Another thing I thought about on the hang issue is that maybe we can
give a timeout for the waits and when the timeout triggers before a
directly assert in the test case we send sigabrt to QEMU (just like
what kill_qemu does) then we could have a chance to see the cores.
Not sure whether that could help, though.

Regards,

-- 
Peter Xu

Re: [PATCH 0/2] migration test tweeks

Posted by Dr. David Alan Gilbert 4 years, 7 months ago

* Peter Xu (peterx@redhat.com) wrote:
> On Mon, Sep 23, 2019 at 02:10:20PM +0100, Dr. David Alan Gilbert (git) wrote:
> > From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> > 
> > Alex noticed that some of the postcopy tests would occasionally
> > hang; this series adds some checks to make them more likely
> > to assert than hang in some failure cases, and changes
> > the migration bandwidth so that under load it's much more likely
> > to manage to land in postcopy.
> > 
> > Dr. David Alan Gilbert (2):
> >   tests/migration: Fail on unexpected migration states
> >   tests/migration/postcopy: trim migration bandwidth
> 
> Reviewed-by: Peter Xu <peterx@redhat.com>
> 
> I might be even more aggresive on patch 2 when turning down the
> bandwidth. :)
> 
> Another thing I thought about on the hang issue is that maybe we can
> give a timeout for the waits and when the timeout triggers before a
> directly assert in the test case we send sigabrt to QEMU (just like
> what kill_qemu does) then we could have a chance to see the cores.
> Not sure whether that could help, though.

Yes I might need to add that; I can see there's another hang somewhere
even with these two patches.
(I *think* it's at the end while it's waiting for completion after
resumption - but I've not figured out what's going on yet).

Dave

> Regards,
> 
> -- 
> Peter Xu
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK