deduplicate actions to avoid unnecessary executions in the flow engine#150
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deduplicate actions to avoid unnecessary executions in the flow engine#150
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Pull Request Overview
This PR introduces action deduplication in the flow engine to prevent unnecessary executions and improve performance. The implementation adds a tracking mechanism to avoid enqueueing duplicate actions while they're still pending in the queue.
- Adds a ConcurrentHashMap to track queued actions in BaseActor
- Modifies the post() method to only enqueue actions that aren't already queued
- Adds null checks in ExecutionContext to skip execution when task definitions are null
Reviewed Changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.
| File | Description |
|---|---|
| ExecutionContext.java | Adds null checks for task definitions in prepare() and refresh() methods |
| BaseActor.java | Implements action deduplication using ConcurrentHashMap tracking |
| ExecutionContextTest.java | Adds test cases for null task definition scenarios |
| BaseActorTest.java | Adds comprehensive tests for action deduplication functionality |
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| queuedActions.computeIfAbsent( | ||
| action, | ||
| a -> { | ||
| actions.offer(a); | ||
| return Boolean.TRUE; | ||
| }); |
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Using Boolean.TRUE as a placeholder value in a ConcurrentHashMap<Action, Boolean> is inefficient. Consider using ConcurrentHashMap.newKeySet() or Set instead, which is more semantically correct for tracking presence and avoids unnecessary Boolean objects.
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| private ConcurrentHashMap<Action, Boolean> getQueuedActionsMap(BaseActor actor) throws Exception { | ||
| Field queuedActionsField = BaseActor.class.getDeclaredField("queuedActions"); | ||
| queuedActionsField.setAccessible(true); | ||
| return (ConcurrentHashMap<Action, Boolean>) queuedActionsField.get(actor); | ||
| } |
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Using reflection to access private fields in tests creates brittle coupling and makes refactoring difficult. Consider adding a package-private getter method in BaseActor for testing purposes or restructuring the test to verify behavior through public APIs only.
derek-miller
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Add audit logging for subscription processing pipeline to track rule evaluations, state changes, and signal dispatches for debugging and observability. Key Changes: - New subscription_log table with weekly partitioning and 3-month retention - SubscriptionLogDao with transaction support for audit log creation - Enhanced SubscriptionProcessor with audit logging for rule evaluations - New polymorphic SubscriptionLogDetails with 5 log type implementations - Added test coverage for new models and functionality This provides visibility into subscription processing lifecycle and supports Signal Service requirements for multi-state dispatching.
derek-miller
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Mar 4, 2026
* add a SEL function to check if a param exists and improve the SEL doc (Netflix#118) * fix some warnings from the build (Netflix#120) * add get workflow instances batch endpoint (Netflix#121) * Add a SEL function to get the value of error retries. Also add one example of k8s step to set env. (Netflix#123) * Add a Redis-based InstanceStepConcurrencyHandler implementation. (Netflix#125) * Add a Redis-based InstanceStepConcurrencyHandler implementation. * address the comment * Add postgres based Maestro persistence layer to support postgressql db. (Netflix#119) * Add postgres based Maestro persistence layer to support postgressql db. * Update indexed columns to use the COLLATE "C". * Make this minor update to use JSON instead JSONB to address some tricky cases. Note that Postgres JSONB will not preserve the original order of map field. It might cause troubles in certain cases, e.g. param map order. * update the dependency lock * address the comments * Improve Maestro to retry certain db errors, e.g. connection is closed. (Netflix#127) * Improve Maestro to retry certain db errors, e.g. connection is closed. * fix null pointer issue in the set contains call * Update delete queue config to match the deletion processor timeout. (Netflix#130) * Update delete queue config to match the deletion processor timeout. * address the comment * Explicitly clear the pending action after passing it to the step runtime. (Netflix#131) * Explicitly clear the pending action after passing it to the step runtime. * Add tests to verify that the pending action is reset. * Add comments for the config. * Improve the test a bit. * Fix edge case where unblocking workflow doesn't enqueue job event (Netflix#132) * Fix edge case where unblocking workflow doesn't enqueue job event There is an edge case when we unblock all failed instances in batches and default batch size = 100, the only failed instance was unblocked in first while loop but didn't enqueue a job event because the condition requires unblocked count > 0 (in 1st loop this value is not updated and is still 0). This PR updated the if condition to account for this case. * improve comment * Check if string map param is literal before returning the value. (Netflix#133) * Check if string map param is literal before returning the value. * Add additional endpoints to workflow controller. (Netflix#136) * Check if map param is literal before returning the value. (Netflix#140) * Check if map param is literal before returning the value. * address the comment * Maestro workers should not retry in certain cases (Netflix#141) * While a worker processes a job, the business logic might throw MaestroNotFoundException, e.g. the workflow is deleted. The worker should not retry in this case. * address the comment * fix a corner case during launching a subworkflow if the subworkflow instance already exists (Netflix#142) * getAction logic should not pick up the upstream actions in async execution mode (Netflix#143) * Subworkflow should wake up its child workflow than itself. (Netflix#144) * Improve step runtime to support setting the next polling delay. (Netflix#145) * Invalid job event should be removed from the queue. (Netflix#146) * Invalid job event should be removed from the queue. * address the comment * Improve the queue performance by adding an explicit lock mechanism (Netflix#129) * Improve the queue performance by adding an explicit lock mechanism because SKIP LOCKED does not perform well if there are a large number of rows. * Use a dedicated queue_lock table for locking queue id. * update dependencies field to JSONB so to support first_value() (Netflix#148) * Add while step runtime support (Netflix#147) * add while step runtime to support while loop * address the comments * fix batch loading rollup * Support waking up flow engine with an action code. (Netflix#149) * Support waking up flow engine with an action code. Meaning of action codes are determined by the Task implementation. * address the comment * deduplicate actions to avoid unnecessary executions in the flow engine (Netflix#150) * Implement tag permit support for Maestro. (Netflix#151) * Implement tag permit support for Maestro. * add extra metrics and small improvements related to tag permit feature (Netflix#152) * Jun/unblock event (Netflix#153) * fix missing action and message fields in the unblock event * upgrade dependency locks * Fix an issue for workflow timeout action: when the workflow is timed out, both the workflow instance and its steps should be marked as timeout. * Slightly improve the code readability with additional comments. (Netflix#155) * Fix the http status code in MaestroRuntimeException. (Netflix#156) * Improve the code and a unit test (Netflix#157) * calling Array.free() to release resources in loop cases (Netflix#159) * Improve actors to cancel the scheduled task ping action during activate/wakeup (Netflix#160) * Actor improvement: during activate call, cancel any existing scheduled task ping as activate will schedule a new ping. * Improve the code a bit and add extra unit tests. * fix tag permit release for queued cases (Netflix#161) * Support extension function in SEL Util class. (Netflix#162) * Support extension function in SEL Util class. * Also add a toJson extension function to Maestro SEL expression evaluator. * Address the comments. * Rename testcontainerPostgresDep to testcontainerDep in all build.gradle files To match the renamed dependency in dependencies.gradle after OSS merge * Regenerate all gradle lockfiles after OSS merge Generated by running: ./gradlew build --write-locks -x test -x integrationTest * Add db-type and ownership-timeout properties to production config - Add db-type: postgres to engine.configs (required by OSS) - Add ownership-timeout: 125000 to queue 5 for deletion processor - Tag permit features left disabled (not needed for Airbnb deployment) * Add OSS sync script for merging upstream changes - Prompts for branch name to avoid hardcoding usernames - Fetches latest from origin and oss remotes - Creates branch from origin/main and merges oss/master - Lists conflicts if any, with helpful next steps - Auto-commits if no conflicts detected --------- Co-authored-by: jun-he <jun-he@users.noreply.github.com> Co-authored-by: yingyiz-netflix <yingyiz@netflix.com>
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Pull Request type
./gradlew build --write-locksto refresh dependencies)NOTE: Please remember to run
./gradlew spotlessApplyto fix any format violations.Changes in this PR
deduplicate actions to avoid unnecessary executions in the flow engine