Ted Yu created HBASE-17379: ------------------------------ Summary: Lack of synchronization in CompactionPipeline#getScanners() Key: HBASE-17379 URL: https://issues.apache.org/jira/browse/HBASE-17379 Project: HBase Issue Type: Bug Reporter: Ted Yu Assignee: Ted Yu
>From >https://builds.apache.org/job/PreCommit-HBASE-Build/5053/testReport/org.apache.hadoop.hbase.regionserver/TestHRegionWithInMemoryFlush/testWritesWhileGetting/ > : {code} java.io.IOException: java.util.ConcurrentModificationException at org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.handleException(HRegion.java:5886) at org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.initializeScanners(HRegion.java:5856) at org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.<init>(HRegion.java:5819) at org.apache.hadoop.hbase.regionserver.HRegion.instantiateRegionScanner(HRegion.java:2786) at org.apache.hadoop.hbase.regionserver.HRegion.getScanner(HRegion.java:2766) at org.apache.hadoop.hbase.regionserver.HRegion.get(HRegion.java:7036) at org.apache.hadoop.hbase.regionserver.HRegion.get(HRegion.java:7015) at org.apache.hadoop.hbase.regionserver.HRegion.get(HRegion.java:6994) at org.apache.hadoop.hbase.regionserver.TestHRegion.testWritesWhileGetting(TestHRegion.java:4141) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47) 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:55) at org.junit.rules.RunRules.evaluate(RunRules.java:20) at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:298) at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:292) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.lang.Thread.run(Thread.java:745) Caused by: java.util.ConcurrentModificationException: null at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:966) at java.util.LinkedList$ListItr.next(LinkedList.java:888) at org.apache.hadoop.hbase.regionserver.CompactionPipeline.getScanners(CompactionPipeline.java:220) at org.apache.hadoop.hbase.regionserver.CompactingMemStore.getScanners(CompactingMemStore.java:298) at org.apache.hadoop.hbase.regionserver.HStore.getScanners(HStore.java:1154) at org.apache.hadoop.hbase.regionserver.Store.getScanners(Store.java:97) at org.apache.hadoop.hbase.regionserver.StoreScanner.getScannersNoCompaction(StoreScanner.java:353) at org.apache.hadoop.hbase.regionserver.StoreScanner.<init>(StoreScanner.java:210) at org.apache.hadoop.hbase.regionserver.HStore.createScanner(HStore.java:1892) at org.apache.hadoop.hbase.regionserver.HStore.getScanner(HStore.java:1880) at org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.initializeScanners(HRegion.java:5842) at org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.<init>(HRegion.java:5819) at org.apache.hadoop.hbase.regionserver.HRegion.instantiateRegionScanner(HRegion.java:2786) at org.apache.hadoop.hbase.regionserver.HRegion.getScanner(HRegion.java:2766) at org.apache.hadoop.hbase.regionserver.HRegion.get(HRegion.java:7036) {code} The cause is in CompactionPipeline#getScanners() where there is no synchronization around iterating pipeline. -- This message was sent by Atlassian JIRA (v6.3.4#6332)