Avoid receive timeout type pollution#3332
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| import scala.concurrent.Await | ||
| import scala.concurrent.duration._ | ||
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| import org.apache.pekko.actor.dungeon.{ ReceiveTimeout => ReceiveTimeoutSupport } |
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can you rebase and fix the imports to be pekko.?
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| // Identify is also an AutoReceivedMessage. Checking its concrete class first avoids polluting its secondary | ||
| // supertype cache on JDKs affected by JDK-8180450 when actor runtime code also checks the AutoReceivedMessage marker. | ||
| @inline def isNotInfluenceReceiveTimeout(message: Any): Boolean = |
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@inline doesn't work for Scala 3. You might need to create a Scala 2 and Scala 3 file with just this method. Better than copy/pasting this whole scala file.
Motivation: The ActorCell receive timeout path allocates on every message and misclassifies timer messages, causing unnecessary timeout rescheduling and state churn. Modification: - Avoid type pollution in the receive timeout hot path - Guard timer receive timeout classification Result: Reduced allocations and correct timeout behavior for actors using receive timeouts. Tests: - Existing ActorCellReceiveTimeoutSpec References: Refs apache#1668
Motivation: The @inline annotation does not work for Scala 3. The JVM JIT will inline this small method regardless of the annotation. Modification: Remove the @inline annotation from isNotInfluenceReceiveTimeout method. Result: Code compiles cleanly on both Scala 2.13 and Scala 3. Performance is unaffected as the JIT compiler will still inline the method. Tests: Not run - annotation removal only, no behavior change References: Refs apache#3332
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Motivation: The @inline annotation does not work for Scala 3. Reviewer requested splitting the method into version-specific files to preserve the inline optimization for Scala 2 while supporting Scala 3. Modification: - Create ReceiveTimeoutCompat object in scala-2.13 with @inline annotation - Create ReceiveTimeoutCompat object in scala-3 with inline keyword - Move isNotInfluenceReceiveTimeout method from ReceiveTimeout to ReceiveTimeoutCompat - Update all call sites to use ReceiveTimeoutCompat Result: Code compiles cleanly on both Scala 2.13 and Scala 3 with appropriate inline optimizations for each version. Tests: sbt "actor-tests/Test/testOnly org.apache.pekko.actor.ReceiveTimeoutSpec" All 14 tests passed. References: Refs apache#3332
Motivation: The isNotInfluenceReceiveTimeout method was moved from ReceiveTimeout to ReceiveTimeoutCompat in the version-specific files, but two call sites still referenced the old location, causing compilation failures across all CI jobs. Modification: Update TimerSchedulerImpl (actor-typed) and ReceiveTimeoutTypePollutionBenchmark (bench-jmh) to reference ReceiveTimeoutCompat.isNotInfluenceReceiveTimeout. Result: All modules compile successfully on both Scala 2.13 and Scala 3. Tests: - sbt "actor-typed / Compile / compileIncremental" (Scala 2.13) - success - sbt "++3.3.8; actor-typed / Compile / compileIncremental" - success References: Refs apache#3332
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Motivation
Identifyimplements bothAutoReceivedMessageandNotInfluenceReceiveTimeout. On JVMs affected by JDK-8180450, alternating successful checks against those two secondary supertypes makes the same concreteKlasssecondary-super cache ping-pong between marker types. The checks occur on the Actor receive-timeout path and can contend across actor-dispatcher threads.The receive path also classified the same message against
NotInfluenceReceiveTimeouttwice.Modification
Identifywith a concrete-class guard before theNotInfluenceReceiveTimeoutmarker check.Result
Receive-timeout behavior remains unchanged, while
Identifyno longer alternates the concrete class secondary-super cache between its two marker interfaces. The final path also performs one classification instead of two.JMH throughput (
ops/us, 12 threads, 3 forks, 5 x 1 s warmup and measurement iterations):JDK 21.0.8 and JDK 25 contain the JVM fix, so their remaining gain primarily measures the removed classification/call rather than secondary-super-cache contention. The JDK 25 result was noisier than the other runs.
References
Refs #1668