Issue #91: Add probabilistic early expiration and TTL jitter#96
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gcloudream wants to merge 1 commit intojhalterman:masterfrom
Open
Issue #91: Add probabilistic early expiration and TTL jitter#96gcloudream wants to merge 1 commit intojhalterman:masterfrom
gcloudream wants to merge 1 commit intojhalterman:masterfrom
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Summary:
Add optional TTL jitter and probabilistic early expiration to reduce cache stampede (#91).
Problem:
Expiration scheduling is deterministic; entries created at the same time with the same TTL expire together, causing a thundering herd.
Fix:
Add
Builder.expirationJitter(jitterPercent)to randomize per-entry TTL on reset.Add
Builder.probabilisticExpiration(probability, windowPercent)to expire early on access when within the last window of TTL.Both features are opt-in; defaults preserve current behavior.
Tests:
Issue91#testProbabilisticEarlyExpiration
Issue91#testExpirationJitterWithinBounds