Efficiency Reporting and Follow-Up Review
Load this reference when the user asks what changed, wants a before/after report, or asks for another pass over remaining expensive jobs.
Reporting Rules
- Separate expected savings from measured savings.
- Do not claim exact time or cost savings without before/after run data.
- Call out confounders such as cache warm-up, changed matrix breadth, runner changes, or unusually small PRs.
Use this phrasing when data is incomplete:
I can report the efficiency mechanisms that changed, but I cannot honestly claim exact minutes saved without comparing before/after GitHub Actions runs.
What To Measure
Gather:
- A baseline sample before the change
- A post-change sample after caches warm
- Per-workflow or per-job duration comparisons
- Avoided runs, skipped jobs, or avoided matrix legs
Always separate:
- PR wall-clock time
- Total runner time across jobs
- Work avoided entirely
These answer different questions. A change can reduce runner spend without materially improving the fastest feedback path.
Follow-Up Review Pass
After the first round of fixes is validated, inspect the remaining expensive jobs:
- Compare setup time versus execution time
- Identify heavyweight wrapper actions and confirm what they really enforce
- Review whether each matrix dimension still serves an active decision
- Recheck after caches warm
- Break down the dominant slow step before proposing further changes
Keep the follow-up compact. Report the next few highest-value opportunities, not a long wishlist.