Hello Users,

I met an issue that is flush times is too long.

MemStoreFlusher is waiting for a lock.
```
"MemStoreFlusher.0"
   java.lang.Thread.State: WAITING (parking)
        at sun.misc.Unsafe.park(Native Method)
        - parking to wait for  <0x00007f0412bddcb8> (a 
java.util.concurrent.locks.ReentrantLock$NonfairSync)
        at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
        at 
java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836)
        at 
java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:870)
        at 
java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1199)
        at 
java.util.concurrent.locks.ReentrantLock$NonfairSync.lock(ReentrantLock.java:209)
        at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:285)
        at 
org.apache.hadoop.hbase.regionserver.StoreScanner.updateReaders(StoreScanner.java:692)
        at 
org.apache.hadoop.hbase.regionserver.HStore.notifyChangedReadersObservers(HStore.java:1100)
        at 
org.apache.hadoop.hbase.regionserver.HStore.updateStorefiles(HStore.java:1079)
        at 
org.apache.hadoop.hbase.regionserver.HStore.access$700(HStore.java:118)
        at 
org.apache.hadoop.hbase.regionserver.HStore$StoreFlusherImpl.commit(HStore.java:2321)
        at 
org.apache.hadoop.hbase.regionserver.HRegion.internalFlushCacheAndCommit(HRegion.java:2430)
        at 
org.apache.hadoop.hbase.regionserver.HRegion.internalFlushcache(HRegion.java:2153)
        at 
org.apache.hadoop.hbase.regionserver.HRegion.internalFlushcache(HRegion.java:2115)
        at 
org.apache.hadoop.hbase.regionserver.HRegion.flushcache(HRegion.java:2005)
        at org.apache.hadoop.hbase.regionserver.HRegion.flush(HRegion.java:1930)
        at 
org.apache.hadoop.hbase.regionserver.MemStoreFlusher.flushRegion(MemStoreFlusher.java:514)
        at 
org.apache.hadoop.hbase.regionserver.MemStoreFlusher.flushRegion(MemStoreFlusher.java:475)
        at 
org.apache.hadoop.hbase.regionserver.MemStoreFlusher.access$900(MemStoreFlusher.java:75)
        at 
org.apache.hadoop.hbase.regionserver.MemStoreFlusher$FlushHandler.run(MemStoreFlusher.java:263)
        at java.lang.Thread.run(Thread.java:748)
   Locked ownable synchronizers:
        - None
```


RPC Handler had the lock.
```
"B.defaultRpcServer.handler"
   java.lang.Thread.State: RUNNABLE
        at org.apache.log4j.Category.getEffectiveLevel(Category.java:442)
        at org.apache.log4j.Category.isEnabledFor(Category.java:751)
        at 
org.apache.commons.logging.impl.Log4JLogger.isTraceEnabled(Log4JLogger.java:303)
        at 
org.apache.hadoop.hdfs.BlockReaderLocal.skip(BlockReaderLocal.java:622)
        - locked <0x00007f0271bcc1c0> (a 
org.apache.hadoop.hdfs.BlockReaderLocal)
        at org.apache.hadoop.hdfs.DFSInputStream.seek(DFSInputStream.java:1534)
        - locked <0x00007f038265f980> (a org.apache.hadoop.hdfs.DFSInputStream)
        at 
org.apache.hadoop.fs.FSDataInputStream.seek(FSDataInputStream.java:62)
        at 
org.apache.hadoop.hbase.io.hfile.HFileUtil.seekOnMultipleSources(HFileUtil.java:38)
        at 
org.apache.hadoop.hbase.io.hfile.HFileBlock$AbstractFSReader.readAtOffset(HFileBlock.java:1431)
        at 
org.apache.hadoop.hbase.io.hfile.HFileBlock$FSReaderImpl.readBlockDataInternal(HFileBlock.java:1654)
        at 
org.apache.hadoop.hbase.io.hfile.HFileBlock$FSReaderImpl.readBlockData(HFileBlock.java:1538)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2.readBlock(HFileReaderV2.java:452)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2$AbstractScannerV2.readNextDataBlock(HFileReaderV2.java:729)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2$ScannerV2.isNextBlock(HFileReaderV2.java:854)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2$ScannerV2.positionForNextBlock(HFileReaderV2.java:849)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2$ScannerV2._next(HFileReaderV2.java:866)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2$ScannerV2.next(HFileReaderV2.java:886)
        at 
org.apache.hadoop.hbase.regionserver.StoreFileScanner.skipKVsNewerThanReadpoint(StoreFileScanner.java:247)
        at 
org.apache.hadoop.hbase.regionserver.StoreFileScanner.seek(StoreFileScanner.java:194)
        at 
org.apache.hadoop.hbase.regionserver.StoreScanner.seekScanners(StoreScanner.java:350)
        at 
org.apache.hadoop.hbase.regionserver.StoreScanner.resetScannerStack(StoreScanner.java:750)
        at 
org.apache.hadoop.hbase.regionserver.StoreScanner.checkReseek(StoreScanner.java:725)
        at 
org.apache.hadoop.hbase.regionserver.StoreScanner.next(StoreScanner.java:475)
        at 
org.apache.hadoop.hbase.regionserver.KeyValueHeap.next(KeyValueHeap.java:150)
        at 
org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.populateResult(HRegion.java:5824)
        at 
org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.nextInternal(HRegion.java:5994)
        at 
org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.nextRaw(HRegion.java:5761)
        at 
org.apache.hadoop.hbase.regionserver.RSRpcServices.scan(RSRpcServices.java:2622)
        - locked <0x00007f035a4df0f8> (a 
org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl)
        at 
org.apache.hadoop.hbase.protobuf.generated.ClientProtos$ClientService$2.callBlockingMethod(ClientProtos.java:33770)
        at org.apache.hadoop.hbase.ipc.RpcServer.call(RpcServer.java:2216)
        at org.apache.hadoop.hbase.ipc.CallRunner.run(CallRunner.java:112)
        at 
org.apache.hadoop.hbase.ipc.RpcExecutor.consumerLoop(RpcExecutor.java:133)
        at org.apache.hadoop.hbase.ipc.RpcExecutor$1.run(RpcExecutor.java:108)
        at java.lang.Thread.run(Thread.java:748)
   Locked ownable synchronizers:
        - <0x00007f02bfaf7a90> (a 
java.util.concurrent.locks.ReentrantLock$NonfairSync)
        - <0x00007f0412bddcb8> (a 
java.util.concurrent.locks.ReentrantLock$NonfairSync)
```

```
B.defaultRpcServer.handler
   java.lang.Thread.State: RUNNABLE
        at java.io.FilterInputStream.read(FilterInputStream.java:83)
        at 
org.apache.hadoop.io.compress.BlockDecompressorStream.rawReadInt(BlockDecompressorStream.java:145)
        at 
org.apache.hadoop.io.compress.BlockDecompressorStream.decompress(BlockDecompressorStream.java:74)
        at 
org.apache.hadoop.io.compress.DecompressorStream.read(DecompressorStream.java:85)
        at java.io.BufferedInputStream.read1(BufferedInputStream.java:284)
        at java.io.BufferedInputStream.read(BufferedInputStream.java:345)
        - locked <0x00007f024acf0bf8> (a java.io.BufferedInputStream)
        at org.apache.hadoop.io.IOUtils.readFully(IOUtils.java:200)
        at 
org.apache.hadoop.hbase.io.compress.Compression.decompress(Compression.java:453)
        at 
org.apache.hadoop.hbase.io.encoding.HFileBlockDefaultDecodingContext.prepareDecoding(HFileBlockDefaultDecodingContext.java:90)
        at 
org.apache.hadoop.hbase.io.hfile.HFileBlock.unpack(HFileBlock.java:549)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2.readBlock(HFileReaderV2.java:455)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2$AbstractScannerV2.readNextDataBlock(HFileReaderV2.java:729)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2$ScannerV2.isNextBlock(HFileReaderV2.java:854)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2$ScannerV2.positionForNextBlock(HFileReaderV2.java:849)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2$ScannerV2._next(HFileReaderV2.java:866)
        at 
org.apache.hadoop.hbase.io.hfile.HFileReaderV2$ScannerV2.next(HFileReaderV2.java:886)
        at 
org.apache.hadoop.hbase.regionserver.StoreFileScanner.skipKVsNewerThanReadpoint(StoreFileScanner.java:247)
        at 
org.apache.hadoop.hbase.regionserver.StoreFileScanner.seek(StoreFileScanner.java:194)
        at 
org.apache.hadoop.hbase.regionserver.StoreScanner.seekScanners(StoreScanner.java:350)
        at 
org.apache.hadoop.hbase.regionserver.StoreScanner.resetScannerStack(StoreScanner.java:750)
        at 
org.apache.hadoop.hbase.regionserver.StoreScanner.checkReseek(StoreScanner.java:725)
        at 
org.apache.hadoop.hbase.regionserver.StoreScanner.next(StoreScanner.java:475)
        at 
org.apache.hadoop.hbase.regionserver.KeyValueHeap.next(KeyValueHeap.java:150)
        at 
org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.populateResult(HRegion.java:5824)
        at 
org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.nextInternal(HRegion.java:5994)
        at 
org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.nextRaw(HRegion.java:5761)
        at 
org.apache.hadoop.hbase.regionserver.RSRpcServices.scan(RSRpcServices.java:2622)
        - locked <0x00007f035a4df0f8> (a 
org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl)
        at 
org.apache.hadoop.hbase.protobuf.generated.ClientProtos$ClientService$2.callBlockingMethod(ClientProtos.java:33770)
        at org.apache.hadoop.hbase.ipc.RpcServer.call(RpcServer.java:2216)
        at org.apache.hadoop.hbase.ipc.CallRunner.run(CallRunner.java:112)
        at 
org.apache.hadoop.hbase.ipc.RpcExecutor.consumerLoop(RpcExecutor.java:133)
        at org.apache.hadoop.hbase.ipc.RpcExecutor$1.run(RpcExecutor.java:108)
        at java.lang.Thread.run(Thread.java:748)
   Locked ownable synchronizers:
        - <0x00007f0412bddcb8> (a 
java.util.concurrent.locks.ReentrantLock$NonfairSync)
```

Versions:
- HBase: 1.2.9
- HDFS: 2.7.7

Best regards,
Minwoo Kang

Reply via email to