TEST — extended cache fix performance experiment (do not merge)#27
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joaodinissf wants to merge 1 commit into
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TEST — extended cache fix performance experiment (do not merge)#27joaodinissf wants to merge 1 commit into
joaodinissf wants to merge 1 commit into
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The maven-verify cache never hit in practice, for three compounding reasons
(verified against the live cache inventory):
- actions/cache only restores on an exact key match, and the key embeds
hashFiles('**/pom.xml') — so any pom-touching PR missed outright.
- GitHub isolates caches per PR scope: the eight open PRs each held a
byte-identical 704 MB cache under their own refs/pull/N/merge, invisible
to one another. The only shareable scope is master, and verify.yml (a
pull_request-only workflow) never saved there.
- master DOES have a cache producer — snapshot.yml saves ~/.m2/repository
as Linux-maven-publish-* on every push — but verify's restore prefix
(Linux-maven-0-) could never match that family. snapshot.yml's own
restore-keys already reach down into Linux-maven-0-; the sharing was
one-directional by accident.
- The redundant per-PR saves pushed the repo over its 10 GB cache budget
(10.35 GB across 14 caches), so LRU eviction also killed same-PR reuse.
Fix, all in the one cache step: switch to actions/cache/restore (PRs stop
saving — ends the duplicate-cache churn and the eviction pressure), add
restore-keys with prefix fallback, and include Linux-maven-publish- so every
PR warm-starts from the snapshot build's superset cache, refreshed on each
merge to master. The maven-0 epoch remains the manual bust lever.
Mechanism verified in a fork experiment (#26): a pom-touching
second run logged 'Cache restored from key: Linux-maven-0-…' and round-
tripped the cached content.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Fork-only A/B experiment for dsldevkit#1399 (extended): run 1 = cold maven-verify (no caches); then the cache-producer dispatch populates a Linux-maven-publish-test-* cache on the base branch scope; run 2 = re-run, expecting 'Cache restored from key: Linux-maven-publish-test-…' and a measurably shorter maven-verify. Will be closed and cleaned up.