Skip to content

Comments

Revert commit "Add a namespace label to admission metrics and expand histogram range to 0-10s"#104033

Merged
k8s-ci-robot merged 1 commit intokubernetes:masterfrom
s-urbaniak:revert-101208-admission_metrics
Jul 30, 2021
Merged

Revert commit "Add a namespace label to admission metrics and expand histogram range to 0-10s"#104033
k8s-ci-robot merged 1 commit intokubernetes:masterfrom
s-urbaniak:revert-101208-admission_metrics

Conversation

@s-urbaniak
Copy link
Contributor

@s-urbaniak s-urbaniak commented Jul 30, 2021 •
edited by liggitt
Loading

/kind bug

What this PR does / why we need it:

By adding a namespace label to admission metrics we found that prometheus will be overwhelmed with out of memory errors within seconds due to amplified cardinality issues. This caused OOMs, raised memory usage in Prometheus from ~1,5GiB RAM steady usage to ~8GiB RAM usage (note, this is for OpenShift).

Which issue(s) this PR fixes:

Fixes #104008

Special notes for your reviewer:

Does this PR introduce a user-facing change?

Revert addition of Add a namespace label to admission metrics and expand histogram range to 0-10s

Fixes a 1.22 regression adding namespace label to admission metrics (and histogram exansion) due to cardinality issues.

@k8s-ci-robot k8s-ci-robot added size/M Denotes a PR that changes 30-99 lines, ignoring generated files. kind/bug Categorizes issue or PR as related to a bug. do-not-merge/release-note-label-needed Indicates that a PR should not merge because it's missing one of the release note labels. do-not-merge/needs-sig Indicates an issue or PR lacks a `sig/foo` label and requires one. needs-triage Indicates an issue or PR lacks a `triage/foo` label and requires one. needs-priority Indicates a PR lacks a `priority/foo` label and requires one. cncf-cla: yes Indicates the PR's author has signed the CNCF CLA. labels Jul 30, 2021
@k8s-ci-robot k8s-ci-robot added area/apiserver sig/api-machinery Categorizes an issue or PR as relevant to SIG API Machinery. sig/instrumentation Categorizes an issue or PR as relevant to SIG Instrumentation. and removed do-not-merge/needs-sig Indicates an issue or PR lacks a `sig/foo` label and requires one. labels Jul 30, 2021
@s-urbaniak s-urbaniak mentioned this pull request Jul 30, 2021
Closed
@k8s-ci-robot k8s-ci-robot added release-note Denotes a PR that will be considered when it comes time to generate release notes. and removed do-not-merge/release-note-label-needed Indicates that a PR should not merge because it's missing one of the release note labels. labels Jul 30, 2021
soltysh
soltysh approved these changes Jul 30, 2021
View reviewed changes
Copy link
Contributor

@soltysh soltysh left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

/lgtm

@k8s-ci-robot k8s-ci-robot added the lgtm "Looks good to me", indicates that a PR is ready to be merged. label Jul 30, 2021
@rphillips
Copy link
Member

rphillips commented Jul 30, 2021

/triage accepted
/priority critical-urgent

@k8s-ci-robot k8s-ci-robot added triage/accepted Indicates an issue or PR is ready to be actively worked on. priority/critical-urgent Highest priority. Must be actively worked on as someone's top priority right now. and removed needs-triage Indicates an issue or PR lacks a `triage/foo` label and requires one. needs-priority Indicates a PR lacks a `priority/foo` label and requires one. labels Jul 30, 2021
lilic
lilic reviewed Jul 30, 2021
View reviewed changes
staging/src/k8s.io/apiserver/pkg/admission/metrics/metrics.go

var (
// Use buckets ranging from 5 ms to 10 seconds (admission webhooks timeout at 30 seconds by default).
latencyBuckets = []float64{0.005, 0.025, 0.1, 0.5, 2.5, 5.0, 10.0}
Copy link
Member

@lilic lilic Jul 30, 2021

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Was the issue the namespace label addition or the extra buckets?

Copy link
Contributor Author

@s-urbaniak s-urbaniak Jul 30, 2021

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

we didn't identify, but the additional buckets for sure amplified the cardinality issue even more. mostly the namespace label is the biggest cardinality contributor.

Copy link

@logicalhan logicalhan Jul 30, 2021

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Primarily, the namespace label..

Copy link
Member

@lilic lilic Jul 30, 2021

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

How many series in total did you observe this added?

Copy link

@logicalhan logicalhan Jul 30, 2021

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

It was the churn from e2e tests. They basically create namespaces on a per-test basis.

Copy link

@logicalhan logicalhan Jul 30, 2021

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

We even have a test which creates 100 namespaces and deletes them.

Copy link

@logicalhan logicalhan Jul 30, 2021

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

https://github.com/kubernetes/kubernetes/blob/master/test/e2e/apimachinery/namespace.go#L246-L251

@lilic
Copy link
Member

lilic commented Jul 30, 2021

cc @kubernetes/sig-instrumentation-approvers

logicalhan
logicalhan approved these changes Jul 30, 2021
View reviewed changes
Copy link

@logicalhan logicalhan left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

/lgtm
/approve

staging/src/k8s.io/apiserver/pkg/admission/metrics/metrics.go

var (
// Use buckets ranging from 5 ms to 10 seconds (admission webhooks timeout at 30 seconds by default).
latencyBuckets = []float64{0.005, 0.025, 0.1, 0.5, 2.5, 5.0, 10.0}
Copy link

@logicalhan logicalhan Jul 30, 2021

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Primarily, the namespace label..

@liggitt
Copy link
Member

liggitt commented Jul 30, 2021

/approve
/milestone v1.22
/kind regression

@k8s-ci-robot k8s-ci-robot added the kind/regression Categorizes issue or PR as related to a regression from a prior release. label Jul 30, 2021
@k8s-ci-robot k8s-ci-robot added this to the v1.22 milestone Jul 30, 2021
@deads2k
Copy link
Contributor

deads2k commented Jul 30, 2021

/approve
/milestone v1.22

@liggitt
Copy link
Member

liggitt commented Jul 30, 2021

please pick to the release-1.22 branch as well and give the @kubernetes/release-managers a heads up that this is incoming

@k8s-ci-robot
Copy link
Contributor

k8s-ci-robot commented Jul 30, 2021

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: deads2k, liggitt, logicalhan, s-urbaniak, soltysh

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

The pull request process is described here

Details Needs approval from an approver in each of these files:

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

@k8s-ci-robot k8s-ci-robot added the approved Indicates a PR has been approved by an approver from all required OWNERS files. label Jul 30, 2021
@k8s-ci-robot k8s-ci-robot merged commit 026fb3b into kubernetes:master Jul 30, 2021
@rphillips rphillips mentioned this pull request Jul 30, 2021
Merged
@rphillips
Copy link
Member

rphillips commented Jul 30, 2021

I gave the slack release-managers a ping and CCed them on the PR.

k8s-ci-robot added a commit that referenced this pull request Jul 30, 2021
@k8s-ci-robot
Merge pull request #104037 from rphillips/automated-cherry-pick-of-#1…
a12ddee 
…04033-upstream-release-1.22

Automated cherry pick of #104033: Revert "Add a namespace label to admission metrics and expand
@openshift-ci-robot openshift-ci-robot mentioned this pull request Aug 2, 2021
Merged
@dgrisonnet dgrisonnet mentioned this pull request Oct 28, 2021
Closed
@aojea aojea mentioned this pull request Mar 9, 2022
Closed
@s-urbaniak s-urbaniak deleted the revert-101208-admission_metrics branch March 9, 2022 12:12
This was referenced Apr 15, 2022
Closed
Closed
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

@soltysh soltysh soltysh approved these changes

@caesarxuchao caesarxuchao Awaiting requested review from caesarxuchao

@sttts sttts Awaiting requested review from sttts

+2 more reviewers

@logicalhan logicalhan logicalhan approved these changes

@lilic lilic lilic left review comments

Reviewers whose approvals may not affect merge requirements

Assignees

@soltysh soltysh

@logicalhan logicalhan

Labels

approved Indicates a PR has been approved by an approver from all required OWNERS files. area/apiserver cncf-cla: yes Indicates the PR's author has signed the CNCF CLA. kind/bug Categorizes issue or PR as related to a bug. kind/regression Categorizes issue or PR as related to a regression from a prior release. lgtm "Looks good to me", indicates that a PR is ready to be merged. priority/critical-urgent Highest priority. Must be actively worked on as someone's top priority right now. release-note Denotes a PR that will be considered when it comes time to generate release notes. sig/api-machinery Categorizes an issue or PR as relevant to SIG API Machinery. sig/instrumentation Categorizes an issue or PR as relevant to SIG Instrumentation. size/M Denotes a PR that changes 30-99 lines, ignoring generated files. triage/accepted Indicates an issue or PR is ready to be actively worked on.

Projects

None yet

Milestone

v1.22

Development

Successfully merging this pull request may close these issues.

apiserver_admission_controller_admission_duration_seconds_bucket is very large in 1.22

8 participants

@s-urbaniak @rphillips @lilic @liggitt @deads2k @k8s-ci-robot @soltysh @logicalhan