org.apache.hadoop.hbase.mob.mapreduce

Class SweepJobNodeTracker

java.lang.Object

org.apache.hadoop.hbase.zookeeper.ZooKeeperListener

org.apache.hadoop.hbase.mob.mapreduce.SweepJobNodeTracker

@InterfaceAudience.Private
public class SweepJobNodeTracker
extends ZooKeeperListener

Tracker on the sweep tool node in zookeeper. The sweep tool node is an ephemeral one, when the process dies this node is deleted, at that time MR might be still running, and if another sweep job is started, two MR for the same column family will run at the same time. This tracker watches this ephemeral node, if it's gone or it's not created by the sweep job that owns the current MR, the current process will be aborted.

Field Summary

Fields inherited from class org.apache.hadoop.hbase.zookeeper.ZooKeeperListener

watcher

Constructor Summary

Constructors

Constructor and Description
SweepJobNodeTracker(ZooKeeperWatcher watcher, String parentNode, String owner)

Method Summary

Modifier and Type	Method and Description
void	nodeDeleted(String path) Called when a node has been deleted
void	start() Registers the watcher on the sweep job node.

Methods inherited from class org.apache.hadoop.hbase.zookeeper.ZooKeeperListener

getWatcher, nodeChildrenChanged, nodeCreated, nodeDataChanged

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SweepJobNodeTracker

public SweepJobNodeTracker(ZooKeeperWatcher watcher,
                           String parentNode,
                           String owner)

Method Detail

start

public void start()
           throws KeeperException

Registers the watcher on the sweep job node. If there's no such a sweep job node, or it's not created by the sweep job that owns the current MR, the current process will be aborted. This assumes the table lock uses the Zookeeper. It's a workaround and only used in the sweep tool, and the sweep tool will be removed after the mob file compaction is finished.

Throws:

KeeperException

nodeDeleted

public void nodeDeleted(String path)

Description copied from class: ZooKeeperListener

Called when a node has been deleted

Overrides:

nodeDeleted in class ZooKeeperListener

Parameters:

path - full path of the deleted node