Post performance results as PR comment

[wojtekn]

Related issues

• N/A

Proposed Changes

• I propose to post performance results as a PR comment, so they are easily available for the PR author and reviewers, without the need to dig into GitHub action logs or CodeVitals charts.

Testing Instructions

• TBD

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[github-actions]

📊 Performance Test Results

Comparing 8c23310 vs trunk

site-editor

Metric	trunk	8c23310	Diff	Change
load	14912.00 ms	14196.00 ms	-716.00 ms	🟢 -4.8%

site-startup

Metric	trunk	8c23310	Diff	Change
siteCreation	18083.00 ms	19178.00 ms	+1095.00 ms	🔴 6.1%
siteStartup	5967.00 ms	4962.00 ms	-1005.00 ms	🟢 -16.8%

---

Results are median values from multiple test runs.

Legend: 🟢 Improvement (faster) | 🔴 Regression (slower) | ⚪ No change

[youknowriad]

I love this. That said if the numbers posted above are not fake, then we have a problem in terms of stability of the CI job :) 42% is huge as a margin of error.

[wojtekn]

@youknowriad I changed rounds to 3, so now it will run each test three times and will use the median value.

It seems much better, and the only downside is that it takes ~30 minutes to complete the suite.

We could consider migrating it to Buildkite at some point.

[youknowriad]

In Gutenberg we had started with 3 and reverted to 1 because we found that it didn't have much impact, now it could be different here :).

[youknowriad]

When you have big diffs like 40% In most cases, I think the issue might be in the test itself, it could be not deterministic enough but it's very hard to find.