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cvo: Verified true boolean not written to cv.status.history during update #179

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merged 2 commits into from
Apr 30, 2019

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smarterclayton
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When we upgrade the CVO causes itself to reboot by updating the
deployment. The CVO gets signalled with SIGTERM and then releases
the leader lease. However, there is no guarantee the latest status
of the CVO has been flushed to the cluster version object which
can mean the "verified: true" flag that the sync worker calculates
when it retrieves the payload doesn't get written. The new CVO pod
loads from the payload and so doesn't have the verified flag.

While in the future we may want to completely decouple verification
from payload retrieval (background worker that verifies available
updates as well as checks historical records), for now we need to
ensure the loaded state is persisted to the CV. Since there may be
useful human information available about the payload that a failed
new CVO pod might not get a chance to write, alter the CVO sync
loop to perform one final status sync during shutdown, and increase
the amount of time we wait before hard shutdown to 5s to give it
more room to happen.

@openshift-ci-robot openshift-ci-robot added approved Indicates a PR has been approved by an approver from all required OWNERS files. size/S Denotes a PR that changes 10-29 lines, ignoring generated files. labels Apr 27, 2019
We flake occasionally when the status the sync worker reports is
partial - since the tests are already waiting to reach level, we
tolerate receiving a status history that is version="", image=X
since the sync worker may have that before it invokes retriev
payload.
@openshift-ci-robot openshift-ci-robot added size/M Denotes a PR that changes 30-99 lines, ignoring generated files. and removed size/S Denotes a PR that changes 10-29 lines, ignoring generated files. labels Apr 27, 2019
@smarterclayton
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/retest

When we upgrade the CVO causes itself to reboot by updating the
deployment. The CVO gets signalled with SIGTERM and then releases
the leader lease. However, there is no guarantee the latest status
of the CVO has been flushed to the cluster version object which
can mean the "verified: true" flag that the sync worker calculates
when it retrieves the payload doesn't get written. The new CVO pod
loads from the payload and so doesn't have the verified flag.

While in the future we may want to completely decouple verification
from payload retrieval (background worker that verifies available
updates as well as checks historical records), for now we need to
ensure the loaded state is persisted to the CV. Since there may be
useful human information available about the payload that a failed
new CVO pod might not get a chance to write, alter the CVO sync
loop to perform one final status sync during shutdown, and increase
the amount of time we wait before hard shutdown to 5s to give it
more room to happen.
@abhinavdahiya
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/lgtm

Nice catch this would have been difficult to track down in the wild ;)

@openshift-ci-robot openshift-ci-robot added the lgtm Indicates that a PR is ready to be merged. label Apr 29, 2019
@openshift-ci-robot
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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: abhinavdahiya, smarterclayton

The full list of commands accepted by this bot can be found here.

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Needs approval from an approver in each of these files:
  • OWNERS [abhinavdahiya,smarterclayton]

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Approvers can cancel approval by writing /approve cancel in a comment

@openshift-merge-robot openshift-merge-robot merged commit faf524c into openshift:master Apr 30, 2019
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 4, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

I'm also pushing the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 4, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

I'm also pushing the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 4, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

I'm also pushing the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 4, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Also set terminationGracePeriodSeconds 130 to extend the default 30s
[3], to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Also push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 4, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Also set terminationGracePeriodSeconds 130 to extend the default 30s
[3], to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Also push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 4, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Also drop an unnecessary runCancel() from the "shutting down" branch
of the error collector.  I'd added it in b30aa0e, but you can only
ever get into the "shutting down" branch if runCancel has already been
called.

Also add some logging to the error collector, so it's easier to see
where we are in the collection process from the operator logs.
Although because we only collect errors at the moment, it's not
obvious from the logs exactly what has been collected.

Also set terminationGracePeriodSeconds 130 to extend the default 30s
[3], to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Also push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 5, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Also drop an unnecessary runCancel() from the "shutting down" branch
of the error collector.  I'd added it in b30aa0e, but you can only
ever get into the "shutting down" branch if runCancel has already been
called.  And fix the scoping for the shutdownTimer variable so we
don't clear it on each for-loop iteration (oops :p, bug from
b30aa0e).

Also add some logging to the error collector, so it's easier to see
where we are in the collection process from the operator logs.
Although because we only collect errors at the moment, it's not
obvious from the logs exactly what has been collected.

Also set terminationGracePeriodSeconds 130 to extend the default 30s
[3], to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Also push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 5, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Decouple shutdownContext from the context passed into Options.run, to
allow TestIntegrationCVO_gracefulStepDown to request a graceful
shutdown.  And remove Context.Start(), inlining the logic in
Options.run so we can count and reap the goroutines it used to launch.
This also allows us to be more targeted with the context for each
goroutines:

* Informers are now launched before the lease controller, so they're
  up and running by the time we acquire the lease.  They remain
  running until the main operator CVO.Run() exits, after which we shut
  them down.  Having informers running before we have a lease is
  somewhat expensive in terms of API traffic, but we should rarely
  have two CVO pods competing for leadership since we transitioned to
  the Recreate Deployment strategy in 078686d
  (install/0000_00_cluster-version-operator_03_deployment: Set
  'strategy: Recreate', 2019-03-20, openshift#140) and 5d8a527
  (install/0000_00_cluster-version-operator_03_deployment: Fix
  Recreate strategy, 2019-04-03, openshift#155).

* The metrics server also continues to run until CVO.Run() exits,
  where previously we began gracefully shutting it down at the same
  time we started shutting down CVO.Run().  This ensures we are around
  and publishing any last-minute CVO.Run() changes.

* Leader election also continues to run until CVO.Run() exits.  We
  don't want to release the lease while we're still controlling
  things.

* CVO.Run() and AutoUpdate.Run() both stop immediately when the
  passed-in context is canceled or we call runCancel internally
  (because of a TERM, error from a goroutine, or loss of leadership).
  These are the only two goroutines that are actually writing to the
  API servers, so we want to shut them down as quickly as possible.

Drop an unnecessary runCancel() from the "shutting down" branch of the
error collector.  I'd added it in b30aa0e, but you can only ever
get into the "shutting down" branch if runCancel has already been
called.  And fix the scoping for the shutdownTimer variable so we
don't clear it on each for-loop iteration (oops :p, bug from
b30aa0e).

Add some logging to the error collector, so it's easier to see where
we are in the collection process from the operator logs.  Also start
logging collected goroutines by name, so we can figure out which may
still be outstanding.

Set terminationGracePeriodSeconds 130 to extend the default 30s [3],
to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 5, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Decouple shutdownContext from the context passed into Options.run, to
allow TestIntegrationCVO_gracefulStepDown to request a graceful
shutdown.  And remove Context.Start(), inlining the logic in
Options.run so we can count and reap the goroutines it used to launch.
This also allows us to be more targeted with the context for each
goroutines:

* Informers are now launched before the lease controller, so they're
  up and running by the time we acquire the lease.  They remain
  running until the main operator CVO.Run() exits, after which we shut
  them down.  Having informers running before we have a lease is
  somewhat expensive in terms of API traffic, but we should rarely
  have two CVO pods competing for leadership since we transitioned to
  the Recreate Deployment strategy in 078686d
  (install/0000_00_cluster-version-operator_03_deployment: Set
  'strategy: Recreate', 2019-03-20, openshift#140) and 5d8a527
  (install/0000_00_cluster-version-operator_03_deployment: Fix
  Recreate strategy, 2019-04-03, openshift#155).

* The metrics server also continues to run until CVO.Run() exits,
  where previously we began gracefully shutting it down at the same
  time we started shutting down CVO.Run().  This ensures we are around
  and publishing any last-minute CVO.Run() changes.

* Leader election also continues to run until CVO.Run() exits.  We
  don't want to release the lease while we're still controlling
  things.

* CVO.Run() and AutoUpdate.Run() both stop immediately when the
  passed-in context is canceled or we call runCancel internally
  (because of a TERM, error from a goroutine, or loss of leadership).
  These are the only two goroutines that are actually writing to the
  API servers, so we want to shut them down as quickly as possible.

Drop an unnecessary runCancel() from the "shutting down" branch of the
error collector.  I'd added it in b30aa0e, but you can only ever
get into the "shutting down" branch if runCancel has already been
called.  And fix the scoping for the shutdownTimer variable so we
don't clear it on each for-loop iteration (oops :p, bug from
b30aa0e).

Add some logging to the error collector, so it's easier to see where
we are in the collection process from the operator logs.  Also start
logging collected goroutines by name, so we can figure out which may
still be outstanding.

Set terminationGracePeriodSeconds 130 to extend the default 30s [3],
to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 5, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Decouple shutdownContext from the context passed into Options.run, to
allow TestIntegrationCVO_gracefulStepDown to request a graceful
shutdown.  And remove Context.Start(), inlining the logic in
Options.run so we can count and reap the goroutines it used to launch.
This also allows us to be more targeted with the context for each
goroutines:

* Informers are now launched before the lease controller, so they're
  up and running by the time we acquire the lease.  They remain
  running until the main operator CVO.Run() exits, after which we shut
  them down.  Having informers running before we have a lease is
  somewhat expensive in terms of API traffic, but we should rarely
  have two CVO pods competing for leadership since we transitioned to
  the Recreate Deployment strategy in 078686d
  (install/0000_00_cluster-version-operator_03_deployment: Set
  'strategy: Recreate', 2019-03-20, openshift#140) and 5d8a527
  (install/0000_00_cluster-version-operator_03_deployment: Fix
  Recreate strategy, 2019-04-03, openshift#155).  I don't see a way to block on
  their internal goroutine's completion, but maybe informers will grow
  an API for that in the future.

* The metrics server also continues to run until CVO.Run() exits,
  where previously we began gracefully shutting it down at the same
  time we started shutting down CVO.Run().  This ensures we are around
  and publishing any last-minute CVO.Run() changes.

* Leader election also continues to run until CVO.Run() exits.  We
  don't want to release the lease while we're still controlling
  things.

* CVO.Run() and AutoUpdate.Run() both stop immediately when the
  passed-in context is canceled or we call runCancel internally
  (because of a TERM, error from a goroutine, or loss of leadership).
  These are the only two goroutines that are actually writing to the
  API servers, so we want to shut them down as quickly as possible.

Drop an unnecessary runCancel() from the "shutting down" branch of the
error collector.  I'd added it in b30aa0e, but you can only ever
get into the "shutting down" branch if runCancel has already been
called.  And fix the scoping for the shutdownTimer variable so we
don't clear it on each for-loop iteration (oops :p, bug from
b30aa0e).

Add some logging to the error collector, so it's easier to see where
we are in the collection process from the operator logs.  Also start
logging collected goroutines by name, so we can figure out which may
still be outstanding.

Set terminationGracePeriodSeconds 130 to extend the default 30s [3],
to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core

squash! pkg/start: Release leader lease on graceful shutdown
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 5, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Decouple shutdownContext from the context passed into Options.run, to
allow TestIntegrationCVO_gracefulStepDown to request a graceful
shutdown.  And remove Context.Start(), inlining the logic in
Options.run so we can count and reap the goroutines it used to launch.
This also allows us to be more targeted with the context for each
goroutines:

* Informers are now launched before the lease controller, so they're
  up and running by the time we acquire the lease.  They remain
  running until the main operator CVO.Run() exits, after which we shut
  them down.  Having informers running before we have a lease is
  somewhat expensive in terms of API traffic, but we should rarely
  have two CVO pods competing for leadership since we transitioned to
  the Recreate Deployment strategy in 078686d
  (install/0000_00_cluster-version-operator_03_deployment: Set
  'strategy: Recreate', 2019-03-20, openshift#140) and 5d8a527
  (install/0000_00_cluster-version-operator_03_deployment: Fix
  Recreate strategy, 2019-04-03, openshift#155).  I don't see a way to block on
  their internal goroutine's completion, but maybe informers will grow
  an API for that in the future.

* The metrics server also continues to run until CVO.Run() exits,
  where previously we began gracefully shutting it down at the same
  time we started shutting down CVO.Run().  This ensures we are around
  and publishing any last-minute CVO.Run() changes.

* Leader election also continues to run until CVO.Run() exits.  We
  don't want to release the lease while we're still controlling
  things.

* CVO.Run() and AutoUpdate.Run() both stop immediately when the
  passed-in context is canceled or we call runCancel internally
  (because of a TERM, error from a goroutine, or loss of leadership).
  These are the only two goroutines that are actually writing to the
  API servers, so we want to shut them down as quickly as possible.

Drop an unnecessary runCancel() from the "shutting down" branch of the
error collector.  I'd added it in b30aa0e, but you can only ever
get into the "shutting down" branch if runCancel has already been
called.  And fix the scoping for the shutdownTimer variable so we
don't clear it on each for-loop iteration (oops :p, bug from
b30aa0e).

Add some logging to the error collector, so it's easier to see where
we are in the collection process from the operator logs.  Also start
logging collected goroutines by name, so we can figure out which may
still be outstanding.

Set terminationGracePeriodSeconds 130 to extend the default 30s [3],
to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core

squash! pkg/start: Release leader lease on graceful shutdown
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 5, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Decouple shutdownContext from the context passed into Options.run, to
allow TestIntegrationCVO_gracefulStepDown to request a graceful
shutdown.  And remove Context.Start(), inlining the logic in
Options.run so we can count and reap the goroutines it used to launch.
This also allows us to be more targeted with the context for each
goroutines:

* Informers are now launched before the lease controller, so they're
  up and running by the time we acquire the lease.  They remain
  running until the main operator CVO.Run() exits, after which we shut
  them down.  Having informers running before we have a lease is
  somewhat expensive in terms of API traffic, but we should rarely
  have two CVO pods competing for leadership since we transitioned to
  the Recreate Deployment strategy in 078686d
  (install/0000_00_cluster-version-operator_03_deployment: Set
  'strategy: Recreate', 2019-03-20, openshift#140) and 5d8a527
  (install/0000_00_cluster-version-operator_03_deployment: Fix
  Recreate strategy, 2019-04-03, openshift#155).  I don't see a way to block on
  their internal goroutine's completion, but maybe informers will grow
  an API for that in the future.

* The metrics server also continues to run until CVO.Run() exits,
  where previously we began gracefully shutting it down at the same
  time we started shutting down CVO.Run().  This ensures we are around
  and publishing any last-minute CVO.Run() changes.

* Leader election also continues to run until CVO.Run() exits.  We
  don't want to release the lease while we're still controlling
  things.

* CVO.Run() and AutoUpdate.Run() both stop immediately when the
  passed-in context is canceled or we call runCancel internally
  (because of a TERM, error from a goroutine, or loss of leadership).
  These are the only two goroutines that are actually writing to the
  API servers, so we want to shut them down as quickly as possible.

Drop an unnecessary runCancel() from the "shutting down" branch of the
error collector.  I'd added it in b30aa0e, but you can only ever
get into the "shutting down" branch if runCancel has already been
called.  And fix the scoping for the shutdownTimer variable so we
don't clear it on each for-loop iteration (oops :p, bug from
b30aa0e).

Add some logging to the error collector, so it's easier to see where
we are in the collection process from the operator logs.  Also start
logging collected goroutines by name, so we can figure out which may
still be outstanding.

Set terminationGracePeriodSeconds 130 to extend the default 30s [3],
to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core

squash! pkg/start: Release leader lease on graceful shutdown
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 6, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Decouple shutdownContext from the context passed into Options.run, to
allow TestIntegrationCVO_gracefulStepDown to request a graceful
shutdown.  And remove Context.Start(), inlining the logic in
Options.run so we can count and reap the goroutines it used to launch.
This also allows us to be more targeted with the context for each
goroutines:

* Informers are now launched before the lease controller, so they're
  up and running by the time we acquire the lease.  They remain
  running until the main operator CVO.Run() exits, after which we shut
  them down.  Having informers running before we have a lease is
  somewhat expensive in terms of API traffic, but we should rarely
  have two CVO pods competing for leadership since we transitioned to
  the Recreate Deployment strategy in 078686d
  (install/0000_00_cluster-version-operator_03_deployment: Set
  'strategy: Recreate', 2019-03-20, openshift#140) and 5d8a527
  (install/0000_00_cluster-version-operator_03_deployment: Fix
  Recreate strategy, 2019-04-03, openshift#155).  I don't see a way to block on
  their internal goroutine's completion, but maybe informers will grow
  an API for that in the future.

* The metrics server also continues to run until CVO.Run() exits,
  where previously we began gracefully shutting it down at the same
  time we started shutting down CVO.Run().  This ensures we are around
  and publishing any last-minute CVO.Run() changes.

* Leader election also continues to run until CVO.Run() exits.  We
  don't want to release the lease while we're still controlling
  things.

* CVO.Run() and AutoUpdate.Run() both stop immediately when the
  passed-in context is canceled or we call runCancel internally
  (because of a TERM, error from a goroutine, or loss of leadership).
  These are the only two goroutines that are actually writing to the
  API servers, so we want to shut them down as quickly as possible.

Drop an unnecessary runCancel() from the "shutting down" branch of the
error collector.  I'd added it in b30aa0e, but you can only ever
get into the "shutting down" branch if runCancel has already been
called.  And fix the scoping for the shutdownTimer variable so we
don't clear it on each for-loop iteration (oops :p, bug from
b30aa0e).

Add some logging to the error collector, so it's easier to see where
we are in the collection process from the operator logs.  Also start
logging collected goroutines by name, so we can figure out which may
still be outstanding.

Set terminationGracePeriodSeconds 130 to extend the default 30s [3],
to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core

squash! pkg/start: Release leader lease on graceful shutdown
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 25, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Decouple shutdownContext from the context passed into Options.run, to
allow TestIntegrationCVO_gracefulStepDown to request a graceful
shutdown.  And remove Context.Start(), inlining the logic in
Options.run so we can count and reap the goroutines it used to launch.
This also allows us to be more targeted with the context for each
goroutines:

* Informers are now launched before the lease controller, so they're
  up and running by the time we acquire the lease.  They remain
  running until the main operator CVO.Run() exits, after which we shut
  them down.  Having informers running before we have a lease is
  somewhat expensive in terms of API traffic, but we should rarely
  have two CVO pods competing for leadership since we transitioned to
  the Recreate Deployment strategy in 078686d
  (install/0000_00_cluster-version-operator_03_deployment: Set
  'strategy: Recreate', 2019-03-20, openshift#140) and 5d8a527
  (install/0000_00_cluster-version-operator_03_deployment: Fix
  Recreate strategy, 2019-04-03, openshift#155).  I don't see a way to block on
  their internal goroutine's completion, but maybe informers will grow
  an API for that in the future.

* The metrics server also continues to run until CVO.Run() exits,
  where previously we began gracefully shutting it down at the same
  time we started shutting down CVO.Run().  This ensures we are around
  and publishing any last-minute CVO.Run() changes.

* Leader election also continues to run until CVO.Run() exits.  We
  don't want to release the lease while we're still controlling
  things.

* CVO.Run() and AutoUpdate.Run() both stop immediately when the
  passed-in context is canceled or we call runCancel internally
  (because of a TERM, error from a goroutine, or loss of leadership).
  These are the only two goroutines that are actually writing to the
  API servers, so we want to shut them down as quickly as possible.

Drop an unnecessary runCancel() from the "shutting down" branch of the
error collector.  I'd added it in b30aa0e, but you can only ever
get into the "shutting down" branch if runCancel has already been
called.  And fix the scoping for the shutdownTimer variable so we
don't clear it on each for-loop iteration (oops :p, bug from
b30aa0e).

Add some logging to the error collector, so it's easier to see where
we are in the collection process from the operator logs.  Also start
logging collected goroutines by name, so we can figure out which may
still be outstanding.

Set terminationGracePeriodSeconds 130 to extend the default 30s [3],
to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core

squash! pkg/start: Release leader lease on graceful shutdown
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 25, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Decouple shutdownContext from the context passed into Options.run, to
allow TestIntegrationCVO_gracefulStepDown to request a graceful
shutdown.  And remove Context.Start(), inlining the logic in
Options.run so we can count and reap the goroutines it used to launch.
This also allows us to be more targeted with the context for each
goroutines:

* Informers are now launched before the lease controller, so they're
  up and running by the time we acquire the lease.  They remain
  running until the main operator CVO.Run() exits, after which we shut
  them down.  Having informers running before we have a lease is
  somewhat expensive in terms of API traffic, but we should rarely
  have two CVO pods competing for leadership since we transitioned to
  the Recreate Deployment strategy in 078686d
  (install/0000_00_cluster-version-operator_03_deployment: Set
  'strategy: Recreate', 2019-03-20, openshift#140) and 5d8a527
  (install/0000_00_cluster-version-operator_03_deployment: Fix
  Recreate strategy, 2019-04-03, openshift#155).  I don't see a way to block on
  their internal goroutine's completion, but maybe informers will grow
  an API for that in the future.

* The metrics server also continues to run until CVO.Run() exits,
  where previously we began gracefully shutting it down at the same
  time we started shutting down CVO.Run().  This ensures we are around
  and publishing any last-minute CVO.Run() changes.

* Leader election also continues to run until CVO.Run() exits.  We
  don't want to release the lease while we're still controlling
  things.

* CVO.Run() and AutoUpdate.Run() both stop immediately when the
  passed-in context is canceled or we call runCancel internally
  (because of a TERM, error from a goroutine, or loss of leadership).
  These are the only two goroutines that are actually writing to the
  API servers, so we want to shut them down as quickly as possible.

Drop an unnecessary runCancel() from the "shutting down" branch of the
error collector.  I'd added it in b30aa0e, but you can only ever
get into the "shutting down" branch if runCancel has already been
called.  And fix the scoping for the shutdownTimer variable so we
don't clear it on each for-loop iteration (oops :p, bug from
b30aa0e).

Add some logging to the error collector, so it's easier to see where
we are in the collection process from the operator logs.  Also start
logging collected goroutines by name, so we can figure out which may
still be outstanding.

Set terminationGracePeriodSeconds 130 to extend the default 30s [3],
to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core

squash! pkg/start: Release leader lease on graceful shutdown
wking added a commit to wking/cluster-version-operator that referenced this pull request Aug 27, 2020
So the incoming cluster-version operator doesn't need to wait for the
outgoing operator's lease to expire, which can take a while [1]:

  I0802 10:06:01.056591       1 leaderelection.go:243] attempting to acquire leader lease  openshift-cluster-version/version...
  ...
  I0802 10:07:42.632719       1 leaderelection.go:253] successfully acquired lease openshift-cluster-version/version

and time out the:

  Cluster did not acknowledge request to upgrade in a reasonable time

testcase [2].  Using ReleaseOnCancel has been the plan since
2b81f47 (cvo: Release our leader lease when we are gracefully
terminated, 2019-01-16, openshift#87).  I'm not clear on why it (sometimes?)
doesn't work today.

The discrepancy between the "exit after 2s no matter what" comment and
the 5s After dates back to dbedb7a (cvo: When the CVO restarts,
perform one final sync to write status, 2019-04-27, openshift#179), which
bumped the After from 2s to 5s, but forgot to bump the comment.  I'm
removing that code here in favor of the two-minute timeout from
b30aa0e (pkg/cvo/metrics: Graceful server shutdown, 2020-04-15, openshift#349).
We still exit immediately on a second TERM, for folks who get
impatient waiting for the graceful timeout.

Decouple shutdownContext from the context passed into Options.run, to
allow TestIntegrationCVO_gracefulStepDown to request a graceful
shutdown.  And remove Context.Start(), inlining the logic in
Options.run so we can count and reap the goroutines it used to launch.
This also allows us to be more targeted with the context for each
goroutines:

* Informers are now launched before the lease controller, so they're
  up and running by the time we acquire the lease.  They remain
  running until the main operator CVO.Run() exits, after which we shut
  them down.  Having informers running before we have a lease is
  somewhat expensive in terms of API traffic, but we should rarely
  have two CVO pods competing for leadership since we transitioned to
  the Recreate Deployment strategy in 078686d
  (install/0000_00_cluster-version-operator_03_deployment: Set
  'strategy: Recreate', 2019-03-20, openshift#140) and 5d8a527
  (install/0000_00_cluster-version-operator_03_deployment: Fix
  Recreate strategy, 2019-04-03, openshift#155).  I don't see a way to block on
  their internal goroutine's completion, but maybe informers will grow
  an API for that in the future.

* The metrics server also continues to run until CVO.Run() exits,
  where previously we began gracefully shutting it down at the same
  time we started shutting down CVO.Run().  This ensures we are around
  and publishing any last-minute CVO.Run() changes.

* Leader election also continues to run until CVO.Run() exits.  We
  don't want to release the lease while we're still controlling
  things.

* CVO.Run() and AutoUpdate.Run() both stop immediately when the
  passed-in context is canceled or we call runCancel internally
  (because of a TERM, error from a goroutine, or loss of leadership).
  These are the only two goroutines that are actually writing to the
  API servers, so we want to shut them down as quickly as possible.

Drop an unnecessary runCancel() from the "shutting down" branch of the
error collector.  I'd added it in b30aa0e, but you can only ever
get into the "shutting down" branch if runCancel has already been
called.  And fix the scoping for the shutdownTimer variable so we
don't clear it on each for-loop iteration (oops :p, bug from
b30aa0e).

Add some logging to the error collector, so it's easier to see where
we are in the collection process from the operator logs.  Also start
logging collected goroutines by name, so we can figure out which may
still be outstanding.

Set terminationGracePeriodSeconds 130 to extend the default 30s [3],
to give the container the full two-minute graceful timeout window
before the kubelet steps in with a KILL.

Push the Background() initialization all the way up to the
command-line handler, to make it more obvious that the context is
scoped to the whole 'start' invocation.

[1]: https://storage.googleapis.com/origin-ci-test/pr-logs/pull/25365/pull-ci-openshift-origin-master-e2e-gcp-upgrade/1289853267223777280/artifacts/e2e-gcp-upgrade/pods/openshift-cluster-version_cluster-version-operator-5b6ff896c6-57ppb_cluster-version-operator.log
[2]: https://bugzilla.redhat.com/show_bug.cgi?id=1843505#c7
[3]: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/#podspec-v1-core

Cherry picked from cc1921d (openshift#424), around conflicts due to the lack
of TLS metrics and the Context pivots in 4.5.
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