Bug: Data race in RecoveredEditsOutputSink while closing writers
Status: Resolved | Priority: Critical | Resolution: Fixed
Created: 01/Jul/24 14:27

Hit this error while testing jdk17 locally

{noformat}
Tests run: 37, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 42.3 s <<< FAILURE! - in org.apache.hadoop.hbase.wal.TestWALSplitValueCompression
org.apache.hadoop.hbase.wal.TestWALSplitValueCompression.testEmptyLogFiles  Time elapsed: 0.359 s  <<< ERROR!
java.io.IOException: java.lang.ArrayIndexOutOfBoundsException: Index 1 out of bounds for length 0
        at org.apache.hadoop.hbase.wal.RecoveredEditsOutputSink.closeWriters(RecoveredEditsOutputSink.java:129)
        at org.apache.hadoop.hbase.wal.RecoveredEditsOutputSink.close(RecoveredEditsOutputSink.java:96)
        at org.apache.hadoop.hbase.wal.WALSplitter.splitWAL(WALSplitter.java:416)
        at org.apache.hadoop.hbase.wal.WALSplitter.split(WALSplitter.java:219)
        at org.apache.hadoop.hbase.wal.TestWALSplit.splitAndCount(TestWALSplit.java:529)
        at org.apache.hadoop.hbase.wal.TestWALSplit.testEmptyLogFiles(TestWALSplit.java:563)
        at org.apache.hadoop.hbase.wal.TestWALSplit.testEmptyLogFiles(TestWALSplit.java:548)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.base/java.lang.reflect.Method.invoke(Method.java:568)
        at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:59)
        at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
        at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:56)
        at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
        at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
        at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
        at org.junit.rules.TestWatcher$1.evaluate(TestWatcher.java:61)
        at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
        at org.junit.runners.BlockJUnit4ClassRunner$1.evaluate(BlockJUnit4ClassRunner.java:100)
        at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:366)
        at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:103)
        at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:63)
        at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)
        at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79)
        at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329)
        at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66)
        at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293)
        at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
        at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
        at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:299)
        at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:293)
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
        at java.base/java.lang.Thread.run(Thread.java:840)
Caused by: java.lang.ArrayIndexOutOfBoundsException: Index 1 out of bounds for length 0
        at java.base/java.util.ArrayList.add(ArrayList.java:455)
        at java.base/java.util.ArrayList.add(ArrayList.java:467)
        at org.apache.hadoop.hbase.wal.RecoveredEditsOutputSink.lambda$closeWriters$0(RecoveredEditsOutputSink.java:111)
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
        at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
        ... 1 more
{noformat}

It is a bit strange that we meet ArrayIndexOutOfBounds in ArrayList.add.

Then I noticed that, we use a thread pool to close the writers but splits field is just an ArrayList, which is not thread safe...