asmhatre
a9867c0423
A Spring Boot 4.1.1 module whose test suite is the evidence for the article: 20 tests producing 22 transcripts under docs/output/, plus 12 documentation chapters. Findings the build pins: - @EnableCaching has no exposeProxy attribute; the widely-copied @EnableCaching(exposeProxy = true) does not compile. - Two methods sharing a cache name and an argument type share a key space, and one silently serves the other's answers. - The documented cache-provider detection order does not match CacheType's enum order in 4.1.1: COUCHBASE before INFINISPAN, and CACHE2K before CAFFEINE. - beforeInvocation = true is NOT deferred by TransactionAwareCacheManagerProxy on 7.0.9 - doEvict picks evictIfPresent, which the decorator does not intercept. - Four of five invalid declarations start a clean context and throw at the first call. - Caffeine on the classpath silently displaces the simple provider.
12 lines
486 B
Plaintext
12 lines
486 B
Plaintext
# sync = true is the difference between one slow call and sixteen
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16 threads call the same key at the same instant, cold cache.
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The method sleeps 300 ms.
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@Cacheable("reports") -> 16 invocations
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@Cacheable("syncedReports", sync = true) -> 1 invocation
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Without sync, every thread that arrives during the 300 ms window misses and
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runs the method. That is a cache stampede, and it is worst exactly when the
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cache matters most - right after a restart or an eviction.
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