Fix TestActor initialization race in parallel test startup#8023
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Arkatufus merged 11 commits intoJan 27, 2026
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Add synchronization mechanism to ensure TestActor.PreStart() completes before CreateInitialTestActor returns. This fixes a race condition where the TestActor's Create message hasn't been processed yet when another actor (like PingerActor) tries to send messages to it. Changes: - InternalTestActor: Add optional ManualResetEventSlim parameter that gets signaled in PreStart() when actor initialization is complete - TestKitBase.CreateInitialTestActor: Wait for the init signal before returning, ensuring the actor is fully ready This provides a deterministic fix for ParallelTestActorDeadlockSpec failures that were occurring under high parallelism on Windows CI.
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Wrapped three tests in AssertAllStagesStoppedAsync to ensure proper cleanup of stream stages before tests complete: - QueueSource_should_emit_received_message_to_the_stream - QueueSource_should_reject_elements_when_backpressuring_with_maxBuffer_0 - QueueSource_should_buffer_when_needed (the failing test from PR akkadotnet#8023) The failure "Failed to stop [QueueSourceSpec-920] within [00:00:05]" occurred because stream stages weren't properly stopped when tests ended with just sub.Cancel() without waiting for cleanup.
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Aaronontheweb
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Wrapped three tests in AssertAllStagesStoppedAsync to ensure proper cleanup of stream stages before tests complete: - QueueSource_should_emit_received_message_to_the_stream - QueueSource_should_reject_elements_when_backpressuring_with_maxBuffer_0 - QueueSource_should_buffer_when_needed (the failing test from PR #8023) The failure "Failed to stop [QueueSourceSpec-920] within [00:00:05]" occurred because stream stages weren't properly stopped when tests ended with just sub.Cancel() without waiting for cleanup.
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1. AtLeastOnceDeliveryReceiveActorSpec.PersistentReceive_must_warn_about_unconfirmed_messages - Extended ReceiveWhileAsync timeout from 3s to 5s - Warning is sent after 3 redeliveries at 500ms intervals (1.5s min) - Extra buffer for CI scheduling delays 2. ReplicatorSpecs.Bugfix_Duplicate_Publish - Changed from Within(5s) block with default 3s ExpectMsg timeout - Now uses explicit 5s timeout per probe ExpectMsg call - Cluster gossip can be slow on busy CI 3. UnhandledMessageEventFilterTests.Unhandled_message_should_produce_info_message - Made deterministic by subscribing to UnhandledMessage events - Wait for UnhandledMessage to confirm message was processed - Guarantees Info log has been published before filter checks
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1. AtLeastOnceDeliveryReceiveActorSpec.PersistentReceive_must_warn_about_unconfirmed_messages - Extended ReceiveWhileAsync timeout from 3s to 5s - Warning is sent after 3 redeliveries at 500ms intervals (1.5s min) - Extra buffer for CI scheduling delays 2. ReplicatorSpecs.Bugfix_Duplicate_Publish - Converted to async TestKit methods (ExpectMsgAsync, ExpectNoMsgAsync) - Added explicit 5s timeout for cluster gossip propagation - Removed synchronous ExpectMsg calls 3. UnhandledMessageEventFilterTests.Unhandled_message_should_produce_info_message - Made deterministic by subscribing to UnhandledMessage events - Wait for UnhandledMessage to confirm message was processed - Guarantees Info log has been published before filter checks
Aaronontheweb
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Jan 26, 2026
1. AtLeastOnceDeliveryReceiveActorSpec.PersistentReceive_must_warn_about_unconfirmed_messages - Extended ReceiveWhileAsync timeout from 3s to 5s - Warning is sent after 3 redeliveries at 500ms intervals (1.5s min) - Extra buffer for CI scheduling delays 2. ReplicatorSpecs.Bugfix_Duplicate_Publish - Converted to async TestKit methods (ExpectMsgAsync, ExpectNoMsgAsync) - Added explicit 5s timeout for cluster gossip propagation - Removed synchronous ExpectMsg calls 3. UnhandledMessageEventFilterTests.Unhandled_message_should_produce_info_message - Made deterministic by subscribing to UnhandledMessage events - Wait for UnhandledMessage to confirm message was processed - Guarantees Info log has been published before filter checks
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Aaronontheweb
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Feb 9, 2026
…t#8023) Add synchronization mechanism to ensure TestActor.PreStart() completes before CreateInitialTestActor returns. This fixes a race condition where the TestActor's Create message hasn't been processed yet when another actor (like PingerActor) tries to send messages to it. Changes: - InternalTestActor: Add optional ManualResetEventSlim parameter that gets signaled in PreStart() when actor initialization is complete - TestKitBase.CreateInitialTestActor: Wait for the init signal before returning, ensuring the actor is fully ready This provides a deterministic fix for ParallelTestActorDeadlockSpec failures that were occurring under high parallelism on Windows CI.
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Aaronontheweb
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Feb 9, 2026
Add synchronization mechanism to ensure TestActor.PreStart() completes before CreateInitialTestActor returns. This fixes a race condition where the TestActor's Create message hasn't been processed yet when another actor (like PingerActor) tries to send messages to it. Changes: - InternalTestActor: Add optional ManualResetEventSlim parameter that gets signaled in PreStart() when actor initialization is complete - TestKitBase.CreateInitialTestActor: Wait for the init signal before returning, ensuring the actor is fully ready This provides a deterministic fix for ParallelTestActorDeadlockSpec failures that were occurring under high parallelism on Windows CI.
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Summary
TestActor.PreStart()completes beforeCreateInitialTestActorreturnsCreatemessage hasn't been processed yet when another actor tries to send messages to itChanges
ManualResetEventSlimparameter that gets signaled inPreStart()when actor initialization is completeRoot Cause
When running multiple TestKits in parallel (as in
ParallelTestActorDeadlockSpec), there was a race between:Createmessage being processed (which triggersPreStart())The
ManualResetEventSlimsynchronization ensures step 2 completes beforeCreateInitialTestActorreturns.Test plan