Upgrade knative -> 0.18

[eddie4941]

Changes

The newest knative/pkg release has released some change to how metrics
are generated. In particular, the new code stops generating a metrics
for every resource that is reconciled. This dramatically reduces the
metrics cardinality for the webhook. This ultimately
reduces amount of memory required by the webhook daemons and
greatly improves the usability of the /metrics endpoint as it will not
longer return a metrics for every resource that is reconciled.

fixes: #2872

Submitter Checklist

These are the criteria that every PR should meet, please check them off as you
review them:

• Includes tests (if functionality changed/added)
• Includes docs (if user facing)
• Commit messages follow commit message best practices
• Release notes block has been filled in or deleted (only if no user facing changes)

See the contribution guide for more details.

Double check this list of stuff that's easy to miss:

• If you are adding a new binary/image to the cmd dir, please update
  the release Task to build and release this image.

Reviewer Notes

If API changes are included, additive changes must be approved by at least two OWNERS and backwards incompatible changes must be approved by more than 50% of the OWNERS, and they must first be added in a backwards compatible way.

Release Notes

This release will drop the `resource_name` label from `webhook_request_(count, latencies_bucket)` metrics. This this breaking change with no replacement for those relying on these metrics. The omission of these metrics will improve the overall memory usage of the webhook and the stability of the /metrics endpoint.

[tekton-robot]

Hi @eddie4941. Thanks for your PR.

I'm waiting for a tektoncd member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

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.

[eddie4941]

I tested this with older clusters to make sure the new changes didn't break anything. The results:

version info:

$ kb version
Client Version: version.Info{Major:"1", Minor:"18", GitVersion:"v1.18.6", GitCommit:"dff82dc0de47299ab66c83c626e08b245ab19037", GitTreeState:"clean", BuildDate:"2020-07-16T00:04:31Z", GoVersion:"go1.14.4", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"17", GitVersion:"v1.17.3", GitCommit:"06ad960bfd03b39c8310aaf92d1e7c12ce618213", GitTreeState:"clean", BuildDate:"2020-02-11T18:07:13Z", GoVersion:"go1.13.6", Compiler:"gc", Platform:"linux/amd64"}

Tekton off of master (8ecaa29) includes the resource_name label:

$ http :9090/metrics | grep webhook_request_latencies_bucket | wc -l
      85

$ http :9090/metrics | grep webhook_request_latencies_bucket | grep 'resource_name=' | wc -l
      85

Tekton with new changes doesn't include the resource_name label.

$ http :9090/metrics | grep webhook_request_latencies_bucket | wc -l
      85

$ http :9090/metrics | grep webhook_request_latencies_bucket | grep 'resource_name=' | wc -l
       0

[imjasonh]

/kind feature

[imjasonh]

/ok-to-test

[vdemeester]

/hold
Let's make sure we wait for 0.17 to be release to get this in

[mattmoor]

FWIW:
/lgtm

I was literally just about to start this and my spidey sense prompted me to go look for a PR 🎉

Looking over this I am actually really glad someone else did this as it looks like it required a lot of changes, so thanks for picking up this particularly nasty change 😅

@vdemeester is there a date for 17?

[mattmoor]

I bumped triggers here (imports this): tektoncd/triggers#784

[vdemeester]

@vdemeester is there a date for 17?

Tomorrow 😉

[eddie4941]

@vdemeester Let me know when this is all good to go. In the meantime, Ill try my best to keep it rebased and up to date.

[vdemeester]

It should also fix #3237 if I am not wrong.

[vdemeester]

/hold cancel

[mattmoor]

/lgtm

[mattmoor]

If we can land this, then I will try to fix up my triggers and CLI PRs today/tomorrow

[vdemeester]

/approve

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: vdemeester

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

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [vdemeester]

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

[mattmoor]

@eddie4941 looks like a merge conflict

test/workspace_test.go:253:24: cannot use t (variable of type *\"testing\".T) as context.Context value in argument to setup: missing method Deadline /home/prow/go/src/github.com/tektoncd/pipeline/test/workspace_test.go:253:25: too few arguments in call to setup

[afrittoli]

I thought the fix for this was in knative/pkg v0.17 which is already in tektoncd/pipeline v0.17.... but it looks like it is not.... I just tried on my v0.17 cluster.
So we'll fix this in tektoncd/pipeline v0.18 using knative/pkg v0.18 :D

[mattmoor]

/lgtm

thanks again! 🎉