Major Description
One of our customers' production HBase clusters was periodically throttled by Azure storage, when HBase was archiving old WALs. HMaster aborted the region server and tried to restart it.
However, since the cluster was still being throttled by Azure storage, the upcoming distributed log splitting also failed. Sometimes hbase:meta table was on this region server and finally showed offline, which cause the whole cluster in bad state.
2015-03-01 18:36:45,623 ERROR org.apache.hadoop.hbase.master.HMaster: Region server workernode4.hbaseproddb4001.f5.internal.cloudapp.net,60020,1424845421044 reported a fatal error: ABORTING region server workernode4.hbaseproddb4001.f5.internal.cloudapp.net,60020,1424845421044: IOE in log roller Cause: org.apache.hadoop.fs.azure.AzureException: com.microsoft.windowsazure.storage.StorageException: The server is busy. at org.apache.hadoop.fs.azurenative.AzureNativeFileSystemStore.rename(AzureNativeFileSystemStore.java:2446) at org.apache.hadoop.fs.azurenative.AzureNativeFileSystemStore.rename(AzureNativeFileSystemStore.java:2367) at org.apache.hadoop.fs.azurenative.NativeAzureFileSystem.rename(NativeAzureFileSystem.java:1960) at org.apache.hadoop.hbase.util.FSUtils.renameAndSetModifyTime(FSUtils.java:1719) at org.apache.hadoop.hbase.regionserver.wal.FSHLog.archiveLogFile(FSHLog.java:798) at org.apache.hadoop.hbase.regionserver.wal.FSHLog.cleanOldLogs(FSHLog.java:656) at org.apache.hadoop.hbase.regionserver.wal.FSHLog.rollWriter(FSHLog.java:593) at org.apache.hadoop.hbase.regionserver.LogRoller.run(LogRoller.java:97) at java.lang.Thread.run(Thread.java:745) Caused by: com.microsoft.windowsazure.storage.StorageException: The server is busy. at com.microsoft.windowsazure.storage.StorageException.translateException(StorageException.java:163) at com.microsoft.windowsazure.storage.core.StorageRequest.materializeException(StorageRequest.java:306) at com.microsoft.windowsazure.storage.core.ExecutionEngine.executeWithRetry(ExecutionEngine.java:229) at com.microsoft.windowsazure.storage.blob.CloudBlob.startCopyFromBlob(CloudBlob.java:762) at org.apache.hadoop.fs.azurenative.StorageInterfaceImpl$CloudBlobWrapperImpl.startCopyFromBlob(StorageInterfaceImpl.java:350) at org.apache.hadoop.fs.azurenative.AzureNativeFileSystemStore.rename(AzureNativeFileSystemStore.java:2439) ... 8 more 2015-03-01 18:43:29,072 ERROR org.apache.hadoop.hbase.executor.EventHandler: Caught throwable while processing event M_META_SERVER_SHUTDOWN java.io.IOException: failed log splitting for workernode13.hbaseproddb4001.f5.internal.cloudapp.net,60020,1424845307901, will retry at org.apache.hadoop.hbase.master.handler.MetaServerShutdownHandler.process(MetaServerShutdownHandler.java:71) at org.apache.hadoop.hbase.executor.EventHandler.run(EventHandler.java:128) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) Caused by: org.apache.hadoop.fs.azure.AzureException: com.microsoft.windowsazure.storage.StorageException: The server is busy. at org.apache.hadoop.fs.azurenative.AzureNativeFileSystemStore.rename(AzureNativeFileSystemStore.java:2446) at org.apache.hadoop.fs.azurenative.NativeAzureFileSystem$FolderRenamePending.execute(NativeAzureFileSystem.java:393) at org.apache.hadoop.fs.azurenative.NativeAzureFileSystem.rename(NativeAzureFileSystem.java:1973) at org.apache.hadoop.hbase.master.MasterFileSystem.getLogDirs(MasterFileSystem.java:319) at org.apache.hadoop.hbase.master.MasterFileSystem.splitLog(MasterFileSystem.java:406) at org.apache.hadoop.hbase.master.MasterFileSystem.splitMetaLog(MasterFileSystem.java:302) at org.apache.hadoop.hbase.master.MasterFileSystem.splitMetaLog(MasterFileSystem.java:293) at org.apache.hadoop.hbase.master.handler.MetaServerShutdownHandler.process(MetaServerShutdownHandler.java:64) ... 4 more Caused by: com.microsoft.windowsazure.storage.StorageException: The server is busy. at com.microsoft.windowsazure.storage.StorageException.translateException(StorageException.java:163) at com.microsoft.windowsazure.storage.core.StorageRequest.materializeException(StorageRequest.java:306) at com.microsoft.windowsazure.storage.core.ExecutionEngine.executeWithRetry(ExecutionEngine.java:229) at com.microsoft.windowsazure.storage.blob.CloudBlob.startCopyFromBlob(CloudBlob.java:762) at org.apache.hadoop.fs.azurenative.StorageInterfaceImpl$CloudBlobWrapperImpl.startCopyFromBlob(StorageInterfaceImpl.java:350) at org.apache.hadoop.fs.azurenative.AzureNativeFileSystemStore.rename(AzureNativeFileSystemStore.java:2439) ... 11 more Sun Mar 01 18:59:51 GMT 2015, org.apache.hadoop.hbase.client.RpcRetryingCaller@aa93ac7, org.apache.hadoop.hbase.NotServingRegionException: org.apache.hadoop.hbase.NotServingRegionException: Region hbase:meta,,1 is not online on workernode13.hbaseproddb4001.f5.internal.cloudapp.net,60020,1425235081338 at org.apache.hadoop.hbase.regionserver.HRegionServer.getRegionByEncodedName(HRegionServer.java:2676) at org.apache.hadoop.hbase.regionserver.HRegionServer.getRegion(HRegionServer.java:4095) at org.apache.hadoop.hbase.regionserver.HRegionServer.scan(HRegionServer.java:3076) at org.apache.hadoop.hbase.protobuf.generated.ClientProtos$ClientService$2.callBlockingMethod(ClientProtos.java:28861) at org.apache.hadoop.hbase.ipc.RpcServer.call(RpcServer.java:2008) at org.apache.hadoop.hbase.ipc.CallRunner.run(CallRunner.java:92) at org.apache.hadoop.hbase.ipc.SimpleRpcScheduler.consumerLoop(SimpleRpcScheduler.java:160) at org.apache.hadoop.hbase.ipc.SimpleRpcScheduler.access$000(SimpleRpcScheduler.java:38) at org.apache.hadoop.hbase.ipc.SimpleRpcScheduler$1.run(SimpleRpcScheduler.java:110) at java.lang.Thread.run(Thread.java:745)
When archiving old WALs, WASB will do rename operation by copying src blob to destination blob and deleting the src blob. Copy blob is very costly in Azure storage and during Azure storage gc, it will be highly likely throttled. The throttling by Azure storage usually ends within 15mins. Current WASB retry policy is exponential retry, but only last at most for 2min. Short term fix will be adding a more intensive exponential retry when copy blob is throttled.