[release-3.11] Bug 1890545: Backport Fix decreasing metric counters when reloading HAProxy

[sgreene570]

This PR is the 3.11 backport of openshift/router#179

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The HAProxy router reload process calls CollectNow() in pkg/router/metrics/haproxy/haproxy.go. Currently, CollectNow() does not update e.lastScrape, which means it is possible for the normal scrape function Collect(...) to be called just after CollectNow(), but before HAProxy has actually reloaded, since CollectNow() essentially "resets" the metrics scrape interval.

The idea in this PR is to have CollectNow() set the e.lastScrape time, since CollectNow() is calling scrape() anyways. This will prevent counter metrics from decreasing across reloads since metrics are only saved for reload preservation during CollectNow() to minimize memory usage.

[openshift-ci-robot]

@sgreene570: This pull request references Bugzilla bug 1890545, which is valid. The bug has been moved to the POST state. The bug has been updated to refer to the pull request using the external bug tracker.

3 validation(s) were run on this bug

• bug is open, matching expected state (open)
• bug target release (3.11.z) matches configured target release for branch (3.11.z)
• bug is in the state ASSIGNED, which is one of the valid states (NEW, ASSIGNED, ON_DEV, POST, POST)

Details

In response to this:

[release-3.11] Bug 1890545: Backport Fix decreasing metric counters when reloading HAProxy

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[frobware]

/lgtm

[sgreene570]

/retest

[knobunc]

/approve

[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: frobware, knobunc, sgreene570

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• pkg/router/OWNERS [knobunc]

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[openshift-ci-robot]

@sgreene570: All pull requests linked via external trackers have merged:

• openshift/origin#25623

Bugzilla bug 1890545 has been moved to the MODIFIED state.

Details

In response to this:

[release-3.11] Bug 1890545: Backport Fix decreasing metric counters when reloading HAProxy

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.