feat: reconcile pod ephemeral metadata in parallel

[com6056]

Right now, every pod has it's ephemeral updated serially. When dealing with a large number of pods, this can get to be quite slow, especially when you have things like validating/mutating webhooks that have to run for every request.

This updates it to simply use an errgroup with a default concurrency of 10 to update the pods in parallel, which should greatly speed things up 🎉

Checklist:

• Either (a) I've created an enhancement proposal and discussed it with the community, (b) this is a bug fix, or (c) this is a chore.
• The title of the PR is (a) conventional with a list of types and scopes found here, (b) states what changed, and (c) suffixes the related issues number. E.g. "fix(controller): Updates such and such. Fixes #1234".
• I've signed my commits with DCO
• I have written unit and/or e2e tests for my change. PRs without these are unlikely to be merged.
• My builds are green. Try syncing with master if they are not.
• My organization is added to USERS.md.

[com6056]

Copied verbiage from

argo-rollouts/controller/controller.go

Lines 73 to 86 in a312e28

	// DefaultRolloutThreads is the default number of rollout worker threads to start with the controller
	DefaultRolloutThreads = 10
	// DefaultExperimentThreads is the default number of experiment worker threads to start with the controller
	DefaultExperimentThreads = 10
	// DefaultAnalysisThreads is the default number of analysis worker threads to start with the controller
	DefaultAnalysisThreads = 30
	// DefaultServiceThreads is the default number of service worker threads to start with the controller
	DefaultServiceThreads = 10
	// DefaultIngressThreads is the default number of ingress worker threads to start with the controller
	DefaultIngressThreads = 10

[com6056]

Copied verbiage from

argo-rollouts/cmd/rollouts-controller/main.go

Lines 297 to 301 in a312e28

	command.Flags().IntVar(&rolloutThreads, "rollout-threads", controller.DefaultRolloutThreads, "Set the number of worker threads for the Rollout controller")
	command.Flags().IntVar(&experimentThreads, "experiment-threads", controller.DefaultExperimentThreads, "Set the number of worker threads for the Experiment controller")
	command.Flags().IntVar(&analysisThreads, "analysis-threads", controller.DefaultAnalysisThreads, "Set the number of worker threads for the Experiment controller")
	command.Flags().IntVar(&serviceThreads, "service-threads", controller.DefaultServiceThreads, "Set the number of worker threads for the Service controller")
	command.Flags().IntVar(&ingressThreads, "ingress-threads", controller.DefaultIngressThreads, "Set the number of worker threads for the Ingress controller")

[github-actions]

Published E2E Test Results

  4 files    4 suites   3h 11m 1s ⏱️
113 tests 101 ✅  7 💤 5 ❌
460 runs  424 ✅ 28 💤 8 ❌

For more details on these failures, see this check.

Results for commit da425f4.

♻️ This comment has been updated with latest results.

[github-actions]

Published Unit Test Results

2 295 tests   2 295 ✅  2m 59s ⏱️
  128 suites      0 💤
    1 files        0 ❌

Results for commit da425f4.

♻️ This comment has been updated with latest results.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
17.0% Duplication on New Code

See analysis details on SonarQube Cloud