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On Wed, Jul 23, 2014 at 02:40:02PM +0200, Salvatore Orlando wrote:
> Here I am again bothering you with the state of the full job for Neutron.
> 
> The patch for fixing an issue in nova's server external events extension
> merged yesterday [1]
> We do not have yet enough data points to make a reliable assessment, but of
> out 37 runs since the patch merged, we had "only" 5 failures, which puts
> the failure rate at about 13%
> 
> This is ugly compared with the current failure rate of the smoketest (3%).
> However, I think it is good enough to start making the full job voting at
> least for neutron patches.
> Once we'll be able to bring down failure rate to anything around 5%, we can
> then enable the job everywhere.

I think that sounds like a good plan. I'm also curious how the failure rates
compare to the other non-neutron jobs, that might be a useful comparison too
for deciding when to flip the switch everywhere.

> 
> As much as I hate asymmetric gating, I think this is a good compromise for
> avoiding developers working on other projects are badly affected by the
> higher failure rate in the neutron full job.

So we discussed this during the project meeting a couple of weeks ago [3] and
there was a general agreement that doing it asymmetrically at first would be
better. Everyone should be wary of the potential harms with doing it
asymmetrically and I think priority will be given to fixing issues that block
the neutron gate should they arise.

> I will therefore resume work on [2] and remove the WIP status as soon as I
> can confirm a failure rate below 15% with more data points.
> 

Thanks for keeping on top of this Salvatore. It'll be good to finally be at
least partially gating with a parallel job.

-Matt Treinish

> 
> [1] https://review.openstack.org/#/c/103865/
> [2] https://review.openstack.org/#/c/88289/
[3] http://eavesdrop.openstack.org/meetings/project/2014/project.2014-07-08-21.03.log.html#l-28

> 
> 
> On 10 July 2014 11:49, Salvatore Orlando <sorlando at nicira.com> wrote:
> 
> >
> >
> >
> > On 10 July 2014 11:27, Ihar Hrachyshka <ihrachys at redhat.com> wrote:
> >
> >> -----BEGIN PGP SIGNED MESSAGE-----
> >> Hash: SHA512
> >>
> >> On 10/07/14 11:07, Salvatore Orlando wrote:
> >> > The patch for bug 1329564 [1] merged about 11 hours ago. From [2]
> >> > it seems there has been an improvement on the failure rate, which
> >> > seem to have dropped to 25% from over 40%. Still, since the patch
> >> > merged there have been 11 failures already in the full job out of
> >> > 42 jobs executed in total. Of these 11 failures: - 3 were due to
> >> > problems in the patches being tested - 1 had the same root cause as
> >> > bug 1329564. Indeed the related job started before the patch merged
> >> > but finished after. So this failure "doesn't count". - 1 was for an
> >> > issue introduced about a week ago which actually causing a lot of
> >> > failures in the full job [3]. Fix should be easy for it; however
> >> > given the nature of the test we might even skip it while it's
> >> > fixed. - 3 were for bug 1333654 [4]; for this bug discussion is
> >> > going on on gerrit regarding the most suitable approach. - 3 were
> >> > for lock wait timeout errors. Several people in the community are
> >> > already working on them. I hope this will raise the profile of this
> >> > issue (maybe some might think it's just a corner case as it rarely
> >> > causes failures in smoke jobs, whereas the truth is that error
> >> > occurs but it does not cause job failure because the jobs isn't
> >> > parallel).
> >>
> >> Can you give directions on where to find those lock timeout failures?
> >> I'd like to check logs to see whether they have the same nature as
> >> most other failures (e.g. improper yield under transaction).
> >>
> >
> > This logstash query will give you all occurences of lock wait timeout
> > issues: message:"(OperationalError) (1205, 'Lock wait timeout exceeded; try
> > restarting transaction')" AND tags:"screen-q-svc.txt"
> >
> > The fact that in most cases the build succeeds anyway is misleading,
> > because in many cases these errors occur in RPC handling between agents and
> > servers, and therefore are not detected by tempest. The neutron full job,
> > which is parallel, increases their occurrence because of parallelism - and
> > since API request too occur concurrently it also yields a higher tempest
> > build failure rate.
> >
> > However, as I argued in the past the "lock wait timeout" error should
> > always be treated as an error condition.
> > Eugene has already classified lock wait timeout failures and filed bugs
> > for them a few weeks ago.
> >
> >
> >> >
> >> > Summarizing, I think time is not yet ripe to enable the full job;
> >> > once bug 1333654 is fixed, we should go for it. AFAIK there is no
> >> > way for working around it in gate tests other than disabling
> >> > nova/neutron event reporting, which I guess we don't want to do.
> >> >
> >> > Salvatore
> >> >
> >> > [1] https://review.openstack.org/#/c/105239 [2]
> >> >
> >> http://logstash.openstack.org/#eyJzZWFyY2giOiJidWlsZF9zdGF0dXM6RkFJTFVSRSBBTkQgbWVzc2FnZTpcIkZpbmlzaGVkOiBGQUlMVVJFXCIgQU5EIGJ1aWxkX25hbWU6XCJjaGVjay10ZW1wZXN0LWRzdm0tbmV1dHJvbi1mdWxsXCIgQU5EIGJ1aWxkX2JyYW5jaDpcIm1hc3RlclwiIiwiZmllbGRzIjpbXSwib2Zmc2V0IjowLCJ0aW1lZnJhbWUiOiIxNzI4MDAiLCJncmFwaG1vZGUiOiJjb3VudCIsInRpbWUiOnsiZnJvbSI6IjIwMTQtMDctMTBUMDA6MjQ6NTcrMDA6MDAiLCJ0byI6IjIwMTQtMDctMTBUMDg6MjQ6NTMrMDA6MDAiLCJ1c2VyX2ludGVydmFsIjoiMCJ9LCJzdGFtcCI6MTQwNDk4MjU2MjM2OCwibW9kZSI6IiIsImFuYWx5emVfZmllbGQiOiIifQ==
> >> >
> >> >
> >> [3]
> >> >
> >> http://logstash.openstack.org/#eyJzZWFyY2giOiJtZXNzYWdlOlwiSFRUUEJhZFJlcXVlc3Q6IFVucmVjb2duaXplZCBhdHRyaWJ1dGUocykgJ21lbWJlciwgdmlwLCBwb29sLCBoZWFsdGhfbW9uaXRvcidcIiBBTkQgdGFnczpcInNjcmVlbi1xLXN2Yy50eHRcIiIsImZpZWxkcyI6W10sIm9mZnNldCI6MCwidGltZWZyYW1lIjoiY3VzdG9tIiwiZ3JhcGhtb2RlIjoiY291bnQiLCJ0aW1lIjp7ImZyb20iOiIyMDE0LTA3LTAxVDA4OjU5OjAxKzAwOjAwIiwidG8iOiIyMDE0LTA3LTEwVDA4OjU5OjAxKzAwOjAwIiwidXNlcl9pbnRlcnZhbCI6IjAifSwic3RhbXAiOjE0MDQ5ODI3OTc3ODAsIm1vZGUiOiIiLCJhbmFseXplX2ZpZWxkIjoiIn0=
> >> >
> >> >
> >> [4] https://bugs.launchpad.net/nova/+bug/1333654
> >> >
> >> >
> >> > On 2 July 2014 17:57, Salvatore Orlando <sorlando at nicira.com>
> >> > wrote:
> >> >
> >> >> Hi again,
> >> >>
> >> >> From my analysis most of the failures affecting the neutron full
> >> >> job are because of bugs [1] and [2] for which patch [3] and [4]
> >> >> have been proposed. Both patches address the nova side of the
> >> >> neutron/nova notification system for vif plugging. It is worth
> >> >> noting that these bugs did manifest only in the neutron full job
> >> >> not because of its "full" nature, but because of its "parallel"
> >> >> nature.
> >> >>
> >> >> Openstackers with a good memory will probably remember we fixed
> >> >> the parallel job back in January, before the massive "kernel bug"
> >> >> gate outage [5]. However, since parallel testing was
> >> >> unfortunately never enabled on the smoke job we run on the gate,
> >> >> we allowed new bugs to slip in. For this reason I would recommend
> >> >> the following: - once patches [3] and [4] have been reviewed and
> >> >> merge, re-assess neutron full job failure rate over a period of
> >> >> 48 hours (72 if the period includes at least 24 hours within a
> >> >> weekend - GMT time) - turn neutron full job to voting if the
> >> >> previous step reveals a failure rate below 10%, otherwise go back
> >> >> to the drawing board
> >> >>
> >> >> In my opinion whether the full job should be enabled in an
> >> >> asymmetric fashion or not should be a decision for the QA and
> >> >> Infra teams. Once the full job is made voting there will
> >> >> inevitably be a higher failure rate. An asymmetric gate will not
> >> >> cause backlogs on other projects, so less angry people, but as
> >> >> Matt said it will still allow other bugs to slip in. Personally
> >> >> I'm ok either way.
> >> >>
> >> >> The reason why we're expecting a higher failure rate on the full
> >> >> job is that we have already observed that some "known" bugs, such
> >> >> as the various lock timeout issues affecting neutron tend to show
> >> >> with a higher frequency on the full job because of its parallel
> >> >> nature.
> >> >>
> >> >> Salvatore
> >> >>
> >> >> [1] https://launchpad.net/bugs/1329546 [2]
> >> >> https://launchpad.net/bugs/1333654 [3]
> >> >> https://review.openstack.org/#/c/99182/ [4]
> >> >> https://review.openstack.org/#/c/103865/ [5]
> >> >> https://bugs.launchpad.net/neutron/+bug/1273386
> >> >>
> >> >>
> >> >>
> >> >>
> >> >> On 25 June 2014 23:38, Matthew Treinish <mtreinish at kortar.org>
> >> >> wrote:
> >> >>
> >> >>> On Tue, Jun 24, 2014 at 02:14:16PM +0200, Salvatore Orlando
> >> >>> wrote:
> >> >>>> There is a long standing patch [1] for enabling the neutron
> >> >>>> full job. Little before the Icehouse release date, when we
> >> >>>> first pushed this, the neutron full job had a failure rate of
> >> >>>> less than 10%. However, since has come by, and perceived
> >> >>>> failure rates were higher, we ran again this analysis.
> >> >>>
> >> >>> So I'm not exactly a fan of having the gates be asymmetrical.
> >> >>> It's very easy for breaks to slip in blocking the neutron gate
> >> >>> if it's not voting everywhere. Especially because I think most
> >> >>> people have been trained to ignore the full job because it's
> >> >>> been nonvoting for so long. Is there a particular reason we
> >> >>> just don't switch everything all at once? I think having a
> >> >>> little bit of friction everywhere during the migration is fine.
> >> >>> Especially if we do it way before a milestone. (as opposed to
> >> >>> the original parallel switch which was right before H-3)
> >> >>>
> >> >>>>
> >> >>>> Here are the findings in a nutshell. 1) If we were to enable
> >> >>>> the job today we might expect about a 3-fold increase in
> >> >>>> neutron job failures when compared with the smoke test.
> >> >>> This is
> >> >>>> unfortunately not acceptable and we therefore need to
> >> >>>> identify and fix
> >> >>> the
> >> >>>> issues causing the additional failure rate. 2) However this
> >> >>>> also puts us in a position where if we wait until the failure
> >> >>>> rate drops under a given threshold we might end up chasing a
> >> >>> moving
> >> >>>> target as new issues might be introduced at any time since
> >> >>>> the job is
> >> >>> not
> >> >>>> voting. 3) When it comes to evaluating failure rates for a
> >> >>>> non voting job,
> >> >>> taking
> >> >>>> the rough numbers does not mean anything, as that will take
> >> >>>> in account patches 'in progress' which end up failing the
> >> >>>> tests because of
> >> >>> problems in
> >> >>>> the patch themselves.
> >> >>>>
> >> >>>> Well, that was pretty much a lot for a "nutshell"; however if
> >> >>>> you're not yet bored to death please go on reading.
> >> >>>>
> >> >>>> The data in this post are a bit skewed because of a rise in
> >> >>>> neutron job failures in the past 36 hours. However, this rise
> >> >>>> affects both the full
> >> >>> and
> >> >>>> the smoke job so it does not invalidate what we say here. The
> >> >>>> results
> >> >>> shown
> >> >>>> below are representative of the gate status 12 hours ago.
> >> >>>>
> >> >>>> - Neutron smoke job failure rates (all queues) 24 hours:
> >> >>>> 22.4% 48 hours: 19.3% 7 days: 8.96% - Neutron smoke job
> >> >>>> failure rates (gate queue only): 24 hours: 10.41% 48 hours:
> >> >>>> 10.20% 7 days: 3.53% - Neutron full job failure rate (check
> >> >>>> queue only as it's non voting): 24 hours: 31.54% 48 hours:
> >> >>>> 28.87% 7 days: 25.73%
> >> >>>>
> >> >>>> Check/Gate Ratio between neutron smoke failures 24 hours:
> >> >>>> 2.15 48 hours: 1.89 7 days: 2.53
> >> >>>>
> >> >>>> Estimated job failure rate for neutron full job if it were to
> >> >>>> run in the gate: 24 hours: 14.67% 48 hours: 15.27% 7 days:
> >> >>>> 10.16%
> >> >>>>
> >> >>>> The numbers are therefore not terrible, but definitely not
> >> >>>> good enough; looking at the last 7 days the full job will
> >> >>>> have a failure rate about 3 times higher than the smoke job.
> >> >>>>
> >> >>>> We then took, as it's usual for us when we do this kind of
> >> >>>> evaluation, a window with a reasonable number of failures (41
> >> >>>> in our case), and
> >> >>> analysed
> >> >>>> them in detail.
> >> >>>>
> >> >>>> Of these 41 failures 17 were excluded because of infra
> >> >>>> problems, patches 'in progress', or other transient failures;
> >> >>>> considering that over the
> >> >>> same
> >> >>>> period of time 160 full job runs succeeded this would leave
> >> >>>> us with 24 failures on 184 run, and therefore a failure rate
> >> >>>> of 13.04%, which not
> >> >>> far
> >> >>>> from the estimate.
> >> >>>>
> >> >>>> Let's consider now these 24 'real' falures: A)  2 were for
> >> >>>> the SSH timeout (8.33% of failures, 1.08% of total full
> >> >>> job
> >> >>>> runs). These specific failure is being analyzed to see if a
> >> >>>> specific fingerprint can be found B) 2  (8.33% of failures,
> >> >>>> 1.08% of total full job runs) were for a
> >> >>> failure
> >> >>>> in test load balancer basic, which is actually a test design
> >> >>>> issue and
> >> >>> is
> >> >>>> already being addressed [2] C) 7 (29.16% of failures, 3.81%
> >> >>>> of total full job runs) were for an
> >> >>> issue
> >> >>>> while resizing a server, which has been already spotted and
> >> >>>> has a bug in progress [3] D) 5 (20.83% of failures, 2.72% of
> >> >>>> total full job runs) manifested as a failure in
> >> >>>> test_server_address; however the actual root cause was being
> >> >>>> masked by [4]. A bug has been filed [5]; this is the most
> >> >>>> worrying one
> >> >>> in
> >> >>>> my opinion as there are many cases where the fault happens
> >> >>>> but does not trigger a failure because of the way tempest
> >> >>>> tests are designed. E) 6 are because of our friend lock wait
> >> >>>> timeout. This was initially
> >> >>> filed
> >> >>>> as [6] but since then we've closed it to file more detailed
> >> >>>> bug reports
> >> >>> as
> >> >>>> the lock wait timeout can manifest in various places; Eugene
> >> >>>> is leading
> >> >>> the
> >> >>>> effort on this problem with Kevin B.
> >> >>>>
> >> >>>>
> >> >>>> Summarizing the only failure modes specific to the full job
> >> >>>> seem to be
> >> >>> C &
> >> >>>> D. If we were able to fix those we should reasonably expect a
> >> >>>> failure
> >> >>> rate
> >> >>>> of about 6.5%. That's still almost twice as the smoke job,
> >> >>>> but I deem it acceptable for two reasons: 1- by voting, we
> >> >>>> will avoid new bugs affecting the full job from being
> >> >>>> introduced. it is worth reminding people that any bug
> >> >>>> affecting the full job is likely to affect production
> >> >>>> environments
> >> >>>
> >> >>> +1, this is a very good point.
> >> >>>
> >> >>>> 2- patches failing in the gate will spur neutron developers
> >> >>>> to quickly
> >> >>> find
> >> >>>> a fix. Patches failing a non voting job will cause some
> >> >>>> neutron core
> >> >>> team
> >> >>>> members to write long and boring posts to the mailing list.
> >> >>>>
> >> >>>
> >> >>> Well, you can always hope. :) But, in my experience the error
> >> >>> is often fixed quickly but the lesson isn't learned, so it will
> >> >>> just happen again. That's why I think we should just grit our
> >> >>> teeth and turn it on everywhere.
> >> >>>
> >> >>>> Salvatore
> >> >>>>
> >> >>>>
> >> >>>>
> >> >>>>
> >> >>>> [1] https://review.openstack.org/#/c/88289/ [2]
> >> >>>> https://review.openstack.org/#/c/98065/ [3]
> >> >>>> https://bugs.launchpad.net/nova/+bug/1329546 [4]
> >> >>>> https://bugs.launchpad.net/tempest/+bug/1332414 [5]
> >> >>>> https://bugs.launchpad.net/nova/+bug/1333654 [5]
> >> >>>> https://bugs.launchpad.net/nova/+bug/1283522
> >> >>>
> >> >>> Very cool, thanks for the update Salvatore. I'm very excited to
> >> >>> get this voting.
> >> >>>
> >> >>>
> >> >>> -Matt Treinish
> >> >>>
> >> >>> _______________________________________________ OpenStack-dev
> >> >>> mailing list OpenStack-dev at lists.openstack.org
> >> >>> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
> >> >>>
> >> >>>
> >> >>
> >> >
> >> >>>
> >> >
> >> >
> >> > _______________________________________________ OpenStack-dev
> >> > mailing list OpenStack-dev at lists.openstack.org
> >> > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
> >> >
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> >
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