ml.dmlc.xgboost4j.java

Class RabitTracker

java.lang.Object

ml.dmlc.xgboost4j.java.RabitTracker

All Implemented Interfaces:

Thread.UncaughtExceptionHandler, IRabitTracker

public class RabitTracker
extends Object
implements IRabitTracker

Java implementation of the Rabit tracker to coordinate distributed workers. As a wrapper of the Python Rabit tracker, this implementation does not handle timeout for both start() and waitFor() methods (i.e., the timeout is infinite.) For systems lacking Python environment, or for timeout functionality, consider using the Scala Rabit tracker (ml.dmlc.xgboost4j.scala.rabit.RabitTracker) which does not depend on Python, and provides timeout support. The tracker must be started on driver node before running distributed jobs.

Nested Class Summary

Nested classes/interfaces inherited from interface ml.dmlc.xgboost4j.java.IRabitTracker

IRabitTracker.TrackerStatus

Constructor Summary

Constructors

Constructor and Description
RabitTracker(int numWorkers)
RabitTracker(int numWorkers, String hostIp, String pythonExec)

Method Summary

Modifier and Type	Method and Description
String	getRabitTrackerCommand() visible for testing
Map<String,String>	getWorkerEnvs() Get environments that can be used to pass to worker.
boolean	start(long timeout)
void	stop()
void	uncaughtException(Thread t, Throwable e)
int	waitFor(long timeout)

Methods inherited from class java.lang.Object

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

Constructor Detail

RabitTracker

public RabitTracker(int numWorkers)
             throws XGBoostError

Throws:

XGBoostError

RabitTracker

public RabitTracker(int numWorkers,
                    String hostIp,
                    String pythonExec)
             throws XGBoostError

Throws:

XGBoostError

Method Detail

uncaughtException

public void uncaughtException(Thread t,
                              Throwable e)

Specified by:

uncaughtException in interface Thread.UncaughtExceptionHandler

getWorkerEnvs

public Map<String,String> getWorkerEnvs()

Get environments that can be used to pass to worker.

Specified by:

getWorkerEnvs in interface IRabitTracker

Returns:

The environment settings.

getRabitTrackerCommand

public String getRabitTrackerCommand()

visible for testing

stop

public void stop()

Specified by:

stop in interface IRabitTracker

start

public boolean start(long timeout)

Specified by:

start in interface IRabitTracker

waitFor

public int waitFor(long timeout)

Specified by:

waitFor in interface IRabitTracker