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Where a Throwable is being caught, take care to rethrow OutOfMemoryError#37748

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scwhittle wants to merge 1 commit intoapache:masterfrom
scwhittle:rethrow_oom
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Where a Throwable is being caught, take care to rethrow OutOfMemoryError#37748
scwhittle wants to merge 1 commit intoapache:masterfrom
scwhittle:rethrow_oom

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This ensures that they are not swallowed leaving the JVM in possibly broken state.


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Summary of Changes

Hello, I'm Gemini Code Assist1! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request enhances the stability and reliability of Apache Beam's Java runners and SDK components by implementing more robust OutOfMemoryError handling. By explicitly rethrowing OOMs, the system ensures that these critical JVM errors are not inadvertently suppressed or wrapped, which could lead to unpredictable behavior or a corrupted state. This change allows the JVM to respond appropriately to severe memory exhaustion, preventing potential data loss or system crashes and contributing to more resilient pipeline execution.

Highlights

  • Explicit OutOfMemoryError Handling: Introduced explicit catch (OutOfMemoryError oom) blocks in numerous locations across the codebase to ensure that OutOfMemoryErrors are immediately rethrown. This prevents them from being caught by more general catch (Throwable) or catch (Exception) blocks, which could otherwise mask critical memory issues and lead to an unstable JVM state.
  • Refined Exception Catching: Adjusted some try-catch blocks to specifically handle RuntimeException and OutOfMemoryError together, or to broaden a catch (Exception) to catch (Throwable) (after the OOM catch) to ensure comprehensive error handling without swallowing critical JVM errors.
  • Minor Codebase Improvements: Included a minor typo correction in a comment within MemoryMonitor.java for improved clarity.

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Changelog
  • runners/core-java/src/main/java/org/apache/beam/runners/core/SimpleDoFnRunner.java
    • Added explicit OutOfMemoryError catch and rethrow in startBundle().
    • Modified invokeProcessElement() to explicitly catch and rethrow OutOfMemoryError, and changed the subsequent catch from Exception to Throwable.
    • Added explicit OutOfMemoryError catch and rethrow in finishBundle().
  • runners/direct-java/src/main/java/org/apache/beam/runners/direct/DirectRunner.java
    • Refactored exception handling in run() to catch and rethrow RuntimeException and OutOfMemoryError in a combined block, removing a redundant instanceof check.
  • runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/BatchDataflowWorker.java
    • Added explicit OutOfMemoryError catch and rethrow in doWork() before the generic Throwable catch.
  • runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/GroupAlsoByWindowFnRunner.java
    • Refactored exception handling in invokeProcessElement() to explicitly catch RuntimeException before Exception, removing an instanceof check.
  • runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/GroupAlsoByWindowsParDoFn.java
    • Added explicit OutOfMemoryError catch and rethrow within the output processing lambda in createRunner().
  • runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/WorkerCustomSources.java
    • Added explicit OutOfMemoryError catch and rethrow in getReaderProgress() for fraction consumed, consumed parallelism, and remaining parallelism estimations.
  • runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/logging/DataflowWorkerLoggingHandler.java
    • Changed the catch block in reportFailure() from Throwable to Exception.
  • runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/util/JfrInterop.java
    • Added explicit OutOfMemoryError catch and rethrow in the static initializer block.
  • runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/util/MemoryMonitor.java
    • Corrected a typo in a comment from 'risk' to 'risky'.
  • runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/util/common/worker/BatchingShuffleEntryReader.java
    • Modified fillEntries() to catch and rethrow RuntimeException and OutOfMemoryError in a combined block.
  • runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/util/common/worker/WorkProgressUpdater.java
    • Added explicit OutOfMemoryError catch and rethrow in tryCheckpointIfNeeded() and reportProgress().
  • runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/windmill/work/processing/StreamingCommitFinalizer.java
    • Added explicit OutOfMemoryError catch and rethrow within the finalizeCommit runnable in finalizeCommits().
  • runners/java-fn-execution/src/main/java/org/apache/beam/runners/fnexecution/artifact/ArtifactStagingService.java
    • Added explicit OutOfMemoryError catch and rethrow in onNext() when getting the completion future result.
  • runners/java-fn-execution/src/main/java/org/apache/beam/runners/fnexecution/control/ReferenceCountingExecutableStageContextFactory.java
    • Added explicit OutOfMemoryError catch and rethrow in release() when closing the ExecutableStageContext.
  • runners/java-fn-execution/src/main/java/org/apache/beam/runners/fnexecution/environment/EmbeddedEnvironmentFactory.java
    • Added explicit OutOfMemoryError catch and rethrow within the fnHarness.get() runnable in createEnvironment().
  • sdks/java/core/src/main/java/org/apache/beam/sdk/fn/data/BeamFnDataOutboundAggregator.java
    • Added explicit OutOfMemoryError catch and rethrow in flush().
  • sdks/java/core/src/main/java/org/apache/beam/sdk/options/ValueProvider.java
    • Added explicit OutOfMemoryError catch and rethrow in the get() method.
  • sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/ApproximateUnique.java
    • Added explicit OutOfMemoryError catch and rethrow in addInput().
  • sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/display/DisplayData.java
    • Added explicit OutOfMemoryError catch and rethrow in include().
  • sdks/java/core/src/main/java/org/apache/beam/sdk/util/MoreFutures.java
    • Added explicit OutOfMemoryError catch and rethrow in supplyAsync() and runAsync().
  • sdks/java/harness/src/main/java/org/apache/beam/fn/harness/FnApiDoFnRunner.java
    • Added explicit OutOfMemoryError catch and rethrow in outputTo().
  • sdks/java/harness/src/main/java/org/apache/beam/fn/harness/SplittablePairWithRestrictionDoFnRunner.java
    • Added explicit OutOfMemoryError catch and rethrow in outputTo().
  • sdks/java/harness/src/main/java/org/apache/beam/fn/harness/SplittableSplitAndSizeRestrictionsDoFnRunner.java
    • Added explicit OutOfMemoryError catch and rethrow in outputTo().
  • sdks/java/harness/src/main/java/org/apache/beam/fn/harness/SplittableTruncateSizedRestrictionsDoFnRunner.java
    • Added explicit OutOfMemoryError catch and rethrow in outputTo().
  • sdks/java/harness/src/main/java/org/apache/beam/fn/harness/control/ProcessBundleHandler.java
    • Added explicit OutOfMemoryError catch and rethrow in the teardown functions within discard().
  • sdks/java/harness/src/main/java/org/apache/beam/fn/harness/logging/BeamFnLoggingClient.java
    • Added explicit OutOfMemoryError catch and rethrow in drainQueueToStream().
  • sdks/java/harness/src/main/java/org/apache/beam/fn/harness/state/FnApiTimerBundleTracker.java
    • Added explicit OutOfMemoryError catch and rethrow in outputTimers().
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Just one that I don't like. The rest LGTM. I'm also suspicious of how often we catch Throwables, vs having some upleveled retry loop, but I understand that issue is out of scope here.

} catch (OutOfMemoryError oom) {
throw oom;
} catch (Throwable t) {
throw wrapUserCodeException(t);
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I'm not so sure we want to wrap every Throwable here. (and if you don't make that change, you don't need the special case)

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I was making this consistent with start and finish, but I can make them consistent by changing it the other way so that just Exceptions are wrapped :)

There is some risk if customer code is throwing Errors that we are changing behavior, but that seems like bad practice and they could just add catches themselves.

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