Thanks Ted for the link. @Deepti, can you please do test the patch, and report back here or in jira about the findings. We should commit the patch.
Enis On Thu, Jan 7, 2016 at 4:50 PM, Deepti Bhogle <dbho...@connexity.com> wrote: > Yes I think its a similar issue. The JIRA mentions a patch created that > should have the fix for the TableSnapshotScanner, we will check if we can > apply the patch to our current version. > Thanks, > Deepti Bhogle | Senior Software Engineer | Connexity, Inc. > Phone: 858.652.4318 | dbho...@connexity.com > > > > > > > > On 1/7/16, 9:35 AM, "Ted Yu" <yuzhih...@gmail.com> wrote: > > >This seems related: > > > >HBASE-14128 > > > >FYI > > > >On Thu, Jan 7, 2016 at 9:24 AM, Deepti Bhogle <dbho...@connexity.com> > wrote: > > > >> We currently do exactly that. We create multiple instances of > >> TableSnapshotScanner each with a unique dir location against the same > >> snapshot. But doing so gives us the exception mentioned. Does that mean > we > >> can’t run multiple instances at the same time? > >> Deepti Bhogle | Senior Software Engineer | Connexity, Inc. > >> Phone: 858.652.4318 | dbho...@connexity.com > >> > >> > >> > >> > >> > >> > >> > >> On 1/7/16, 3:46 AM, "Enis Söztutar" <e...@apache.org> wrote: > >> > >> >TableSnapshotScanner itself does not support more than one scanner. Are > >> you > >> >creating more than 1 TableSnapshotScanner in your parallel scan? > >> > > >> >Everytime a snapshot scanner is initiated, it will try to "restore" the > >> >snapshot to a temporary location out of the regular root directory in > >> hdfs. > >> >You can try to give different restore directories to each > >> >TableSnapshotScanner. > >> > > >> >Enis > >> > > >> >On Wed, Jan 6, 2016 at 5:51 PM, dbhogle <dbho...@connexity.com> wrote: > >> > > >> >> Using the client api, we can scan the snapshot using a single > scanner. > >> We > >> >> currently create an instance of TableSnapshotScanner providing it > with a > >> >> unique dir location per scanner. We are currently on cdh 5.4.5 and > using > >> >> the > >> >> hbase 1.0.0-cdh5.4.5 api. In order to get desired throughput, we > tried > >> to > >> >> increase the number of parallel scanners but raising the no. of > scanner > >> >> instances throws the following exception, the occurrence increases as > >> the > >> >> no. of scanners goes up. > >> >> Can the client api support multiple scanners for a single snapshot? > >> >> > >> >> java.io.IOException: java.util.concurrent.ExecutionException: > >> >> > >> >> > >> > org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.hdfs.protocol.AlreadyBeingCreatedException): > >> >> failed to create file > >> >> > >> >> > >> > /hbase/archive/data/default/<tableName>/cb794cfb7948ba8b1f4e73b690dfbfe5/L/.links-a04e1a5b2141445eb1b9e2429f1eced2/cb794cfb7948ba8b1f4e73b690dfbfe5.<tableName> > >> >> for DFSClient_NONMAPREDUCE_672650916_1 for client 10.10.2.90 because > >> >> current > >> >> leaseholder is trying to recreate file. > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hdfs.server.namenode.FSNamesystem.recoverLeaseInternal(FSNamesystem.java:3077) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFileInternal(FSNamesystem.java:2783) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFileInt(FSNamesystem.java:2676) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFile(FSNamesystem.java:2560) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.create(NameNodeRpcServer.java:585) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hdfs.server.namenode.AuthorizationProviderProxyClientProtocol.create(AuthorizationProviderProxyClientProtocol.java:110) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.create(ClientNamenodeProtocolServerSideTranslatorPB.java:395) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:619) > >> >> at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:1060) > >> >> at > org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2044) > >> >> at > org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2040) > >> >> at java.security.AccessController.doPrivileged(Native Method) > >> >> at javax.security.auth.Subject.doAs(Subject.java:415) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1671) > >> >> at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2038) > >> >> > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hbase.util.ModifyRegionUtils.createRegions(ModifyRegionUtils.java:162) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hbase.snapshot.RestoreSnapshotHelper.cloneHdfsRegions(RestoreSnapshotHelper.java:561) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hbase.snapshot.RestoreSnapshotHelper.restoreHdfsRegions(RestoreSnapshotHelper.java:237) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hbase.snapshot.RestoreSnapshotHelper.restoreHdfsRegions(RestoreSnapshotHelper.java:159) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hbase.snapshot.RestoreSnapshotHelper.copySnapshotForScanner(RestoreSnapshotHelper.java:812) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hbase.client.TableSnapshotScanner.init(TableSnapshotScanner.java:156) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hbase.client.TableSnapshotScanner.<init>(TableSnapshotScanner.java:124) > >> >> at > >> >> > >> >> > >> > org.apache.hadoop.hbase.client.TableSnapshotScanner.<init>(TableSnapshotScanner.java:101) > >> >> at > >> >> net.connexity.aro.data.AudienceScanner.join(AudienceScanner.scala:68) > >> >> at > >> >> net.connexity.aro.actor.ScanActor.joinAudience(ScanActor.scala:190) > >> >> at > >> >> > >> >> > >> > net.connexity.aro.actor.ScanActor$$anonfun$receive$1.applyOrElse(ScanActor.scala:90) > >> >> at akka.actor.Actor$class.aroundReceive(Actor.scala:467) > >> >> at > >> >> net.connexity.aro.actor.ScanActor.aroundReceive(ScanActor.scala:36) > >> >> at akka.actor.ActorCell.receiveMessage(ActorCell.scala:516) > >> >> at akka.actor.ActorCell.invoke(ActorCell.scala:487) > >> >> at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:238) > >> >> at akka.dispatch.Mailbox.run(Mailbox.scala:220) > >> >> at > >> >> > >> >> > >> > akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:397) > >> >> at > >> >> scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260) > >> >> at > >> >> > >> >> > >> > scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339) > >> >> at > >> >> > scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979) > >> >> at > >> >> > >> >> > >> > scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107) > >> >> > >> >> > >> >> > >> >> -- > >> >> View this message in context: > >> >> > >> > http://apache-hbase.679495.n3.nabble.com/Parallel-scanning-of-snapshots-using-hbase-client-api-tp4077014.html > >> >> Sent from the HBase Developer mailing list archive at Nabble.com. > >> >> > >> >
