Fix WithinAsync timeout not propagating to EventFilter across async boundaries#7977
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Aaronontheweb merged 6 commits intoDec 29, 2025
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…oundaries Use AsyncLocal<TimeSpan?> to properly propagate WithinAsync timeout to EventFilter and other async operations. The previous implementation used a plain instance field (_testState.End) which could have memory visibility issues when accessed from different threads across await boundaries. The fix: - Adds AsyncLocal<TimeSpan?> field that flows through async contexts - WithinAsync sets/restores both instance field and AsyncLocal - Remaining and RemainingOr check AsyncLocal first, then instance field - Preserves backward compatibility with sync code paths
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…oundaries (akkadotnet#7977) * Fix WithinAsync timeout not propagating to EventFilter across async boundaries Use AsyncLocal<TimeSpan?> to properly propagate WithinAsync timeout to EventFilter and other async operations. The previous implementation used a plain instance field (_testState.End) which could have memory visibility issues when accessed from different threads across await boundaries. The fix: - Adds AsyncLocal<TimeSpan?> field that flows through async contexts - WithinAsync sets/restores both instance field and AsyncLocal - Remaining and RemainingOr check AsyncLocal first, then instance field - Preserves backward compatibility with sync code paths * remove `static` --------- Co-authored-by: Gregorius Soedharmo <arkatufus@yahoo.com>
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…oundaries (#7977) * Fix WithinAsync timeout not propagating to EventFilter across async boundaries Use AsyncLocal<TimeSpan?> to properly propagate WithinAsync timeout to EventFilter and other async operations. The previous implementation used a plain instance field (_testState.End) which could have memory visibility issues when accessed from different threads across await boundaries. The fix: - Adds AsyncLocal<TimeSpan?> field that flows through async contexts - WithinAsync sets/restores both instance field and AsyncLocal - Remaining and RemainingOr check AsyncLocal first, then instance field - Preserves backward compatibility with sync code paths * remove `static` --------- Co-authored-by: Gregorius Soedharmo <arkatufus@yahoo.com>
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Summary
WithinAsynctimeout was not reliably propagating toEventFilterand other async operationsAsyncLocal<TimeSpan?>to properly flow timeout across async boundariesRoot Cause
The
_testState.Endfield set byWithinAsyncis a plain instance property without volatile semantics. WhenEventFilterreads this value throughRemainingOrDefaulton a different thread (via async continuation), it could see a stale cache value due to CPU cache coherency delays. This causedEventFilterto occasionally fall back to the default 3000ms timeout instead of the timeout set byWithinAsync.Fix
AsyncLocal<TimeSpan?>field that automatically flows through async contexts viaExecutionContextWithinAsyncnow sets/restores both the instance field (for sync code paths) and the AsyncLocal (for async code paths)Remainingproperty andRemainingOrmethod check AsyncLocal first, then fall back to instance fieldTest plan
WithinAsync_timeout_should_propagate_to_EventFilterpasses consistently (10/10 runs)Akka.TestKit.Testssuite passes (293 passed, 1 skipped, 0 failed)