imagecache: Fix TestConcurrentEnsureImageAndEvict flake - #1079
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Max Thompson (thompsonmax) wants to merge 1 commit into
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imagecache: Fix TestConcurrentEnsureImageAndEvict flake#1079Max Thompson (thompsonmax) wants to merge 1 commit into
Max Thompson (thompsonmax) wants to merge 1 commit into
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The reuse/retire protocol leaves one legitimate window: after ensureLayer refreshes a reused dir's mtime inside the layer singleflight, but before the image record rewrite re-references it, an eviction pass whose cutoff postdates the refresh may retire the dir. The pull's final re-verify caught this and failed the pull into an RPC retry, which TestConcurrentEnsureImageAndEvict (correctly, per its stated invariant) flagged as a flake under CI load. Make the test's invariant true: when the re-verify finds a vanished layer dir, loop back and unpack the missing layers again, bounded to one extra attempt. One retry suffices because the winning pass listed its candidates before our record rewrite, so it cannot retire the re-unpacked dirs, and any later pass sees them referenced. Exhausting the attempts still fails with the original "vanished during pull" error. TestPullReverifyFailsCleanlyOnYankedLayer asserted the old fail-clean behavior; it becomes TestPullReverifyRepullsYankedLayer, asserting the yanked layer is unpacked again and the pull succeeds. Fixes agent-substrate#1076
Zoe Zhao (zoez7)
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area/tests
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Superseded by #1509, will close this PR. |
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The reuse/retire protocol leaves one legitimate window: after ensureLayer refreshes a reused dir's mtime inside the layer singleflight, but before the image record rewrite re-references it, an eviction pass whose cutoff postdates the refresh may retire the dir. The pull's final re-verify caught this and failed the pull into an RPC retry, which TestConcurrentEnsureImageAndEvict (correctly, per its stated invariant) flagged as a flake under CI load.
Make the test's invariant true: when the re-verify finds a vanished layer dir, loop back and unpack the missing layers again, bounded to one extra attempt. One retry suffices because the winning pass listed its candidates before our record rewrite, so it cannot retire the re-unpacked dirs, and any later pass sees them referenced. Exhausting the attempts still fails with the original "vanished during pull" error.
TestPullReverifyFailsCleanlyOnYankedLayer asserted the old fail-clean behavior; it becomes TestPullReverifyRepullsYankedLayer, asserting the yanked layer is unpacked again and the pull succeeds.
Fixes #1076