Implement parallel executor service without ForkJoinPool
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* More precise clock * Fixed width thread names * Abbreviated package names
To avoid race conditions with other workers that lead to stalling.
…on-custom-implementation
mpkorstanje
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No more remarks. LGTM.
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| } | ||
| if (!entriesRequiringResourceLocks.isEmpty()) { | ||
| // One entry at a time to avoid blocking too much | ||
| tryToStealWork(entriesRequiringResourceLocks.get(0), BlockingMode.BLOCKING); |
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Entries can be stolen by other workers so, this restarts scanning the queue from the beginning too early.
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Thought of something.
mpkorstanje
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CI failing on 85ccf17 from |
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This PR introduces a new implementation of
HierarchicalTestExecutorServicethat runs rests in parallel and has limited work stealing capabilities but is not based onForkJoinPool. It avoids its pitfalls (such as #3945) and #3108 but may require additional threads because its work stealing is limited to direct children. Contrary to theForkJoinPoolimplementation, the new executor service guarantees that no more thanparallelismtest nodes are executed in parallel.My intention is to initially ship this implementation as an opt-in feature (via the new
junit.jupiter.execution.parallel.executorconfiguration parameter) in 6.1, make it an opt-out feature in 6.2, and drop support for theForkJoinPool-based implementation in a later to-be-determined release.The PR is not yet finished but feedback is already welcome! If you use parallel test execution in your projects (or other test engines), it would be great if you could try out the new implementation and report your observations.
Resolves #3108.
I hereby agree to the terms of the JUnit Contributor License Agreement.
Definition of Done
@APIannotations