lima.distribution
Class DServer

java.lang.Object
  |
  +--java.rmi.server.RemoteObject
        |
        +--java.rmi.server.RemoteServer
              |
              +--java.rmi.server.UnicastRemoteObject
                    |
                    +--lima.distribution.DServer

All Implemented Interfaces:

Observable, java.rmi.Remote, java.lang.Runnable, java.io.Serializable, WorkUnitProcessor, WorkUnitServer

public class DServer

extends java.rmi.server.UnicastRemoteObject

implements WorkUnitProcessor, WorkUnitServer, java.lang.Runnable, Observable

DServer is the magic that is a Combined WorkUnit Processor and Server. TODO Call alldone at the right time. TODO: What happens if a wu is given up on, then comes back before/after being sent back a (second time) Tested by dc

See Also:

Serialized Form

Nested Class Summary

class	DServer.ClientSpeedUpdateEvent An event indicating that the speed measurement of a client has been updated.
class	DServer.ClientWorkUnitRequestAcceptedEvent An event indicating that a request for a work unit was accepted.
class	DServer.ClientWorkUnitRequestEvent An event indicating that a work unit has been requested.
class	DServer.ClientWorkUnitSubmissionAcceptedEvent An event indicating that a submitted work unit was accepted.
class	DServer.ClientWorkUnitSubmissionEvent An event indicating that a work unit has been submitted.
class	DServer.JobCompletionEvent An event indicating that a job has been completed.
class	DServer.JobCreationEvent An event indicating that a job has been created.
class	DServer.JobFailureEvent An event indicating that a job has failed.
class	DServer.MemoryUsageEvent An event describing the current memory usage.
class	DServer.WorkUnitCountersEvent An event indicating the current work unit counter values.

Field Summary

static int	BESTTIME We aim for clients to turn around a wu in this time The system will try to create cwus that thake this long in real time on a client.
static boolean	DEBUG Set do we want to debug.
static java.lang.String	serverName The name for this server when bound in the RMI Registry.
static boolean	VERBOSE We can also be more verbose about what we are doing.
static int	WAITTIME The longest time to wait for a workunit to be send back If a client takes more than this time before sending the wu back, then we assume that the client has crashed, and schedule it to be resent.

Fields inherited from class java.rmi.server.RemoteObject

ref

Constructor Summary

DServer()
This constructor is needed since the default constructor must throw RemoteException

Method Summary

void	clearObservers() Unregister all observers for an observable object.
static void	main(java.lang.String[] args) Start up a standalone DServer.This is the normal way to create a DServer.
void	notifyObservers(lima.observation.Event event) Notify all registered observers of the specified event.
void	process(lima.distribution.WorkUnitSink sink, lima.distribution.WorkUnitSource source) Do the job defined by source and sink.
void	registerObserver(lima.observation.Observer observer) Register the specified observer with an observable object.
lima.distribution.WorkUnit	requestWorkUnit() Called by the client when it wants more work.
void	run() Implementation provided for clients that require a runnable interface.
void	submitWorkUnit(lima.distribution.WorkUnit u) Called by the client to send back a finished work unit.
java.lang.String	toString() Produce a status string.
void	unregisterObserver(lima.observation.Observer observer) Unregister the specified observer with an observable object.

Methods inherited from class java.rmi.server.UnicastRemoteObject

clone, exportObject, exportObject, exportObject, unexportObject

Methods inherited from class java.rmi.server.RemoteServer

getClientHost, getLog, setLog

Methods inherited from class java.rmi.server.RemoteObject

equals, getRef, hashCode, toStub

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

DEBUG

public static final boolean DEBUG

Set do we want to debug. Yes here will do extra (silent) tests to check sanity

See Also:

Constant Field Values

VERBOSE

public static final boolean VERBOSE

We can also be more verbose about what we are doing. With this on more data is printed to stdout.

See Also:

Constant Field Values

BESTTIME

public static final int BESTTIME

We aim for clients to turn around a wu in this time The system will try to create cwus that thake this long in real time on a client.

See Also:

Constant Field Values

WAITTIME

public static final int WAITTIME

The longest time to wait for a workunit to be send back If a client takes more than this time before sending the wu back, then we assume that the client has crashed, and schedule it to be resent. Note that this can cause a dupe to be received if the client is just very slow.

See Also:

Constant Field Values

serverName

public static final java.lang.String serverName

The name for this server when bound in the RMI Registry.

See Also:

Constant Field Values

Constructor Detail

DServer

public DServer()
        throws java.rmi.RemoteException

This constructor is needed since the default constructor must throw RemoteException

Method Detail

process

public void process(lima.distribution.WorkUnitSink sink,
                    lima.distribution.WorkUnitSource source)
             throws java.rmi.RemoteException

Do the job defined by source and sink.

Specified by:

process in interface WorkUnitProcessor

Parameters:

source - - Provides WorkUnits

sink - - Callback to flush finished workunits.

java.rmi.RemoteException

See Also:

WorkUnitProcessor.process(WorkUnitSink, WorkUnitSource)

requestWorkUnit

public lima.distribution.WorkUnit requestWorkUnit()
                                           throws java.rmi.RemoteException,
                                                  NoWorkException

Called by the client when it wants more work. Returns a wu that will take a roughtly constant time to run.

Specified by:

requestWorkUnit in interface WorkUnitServer

Returns:

WorkUnit - A WorkUnit that needs processing (call run() on it)

java.rmi.RemoteException

NoWorkException

See Also:

WorkUnitServer.requestWorkUnit()

submitWorkUnit

public void submitWorkUnit(lima.distribution.WorkUnit u)
                    throws java.rmi.RemoteException

Called by the client to send back a finished work unit. This is (and all other public methods are synchronized. This means there should only be two threads in this code at one time (the main thread and either a client or a cruncher thread.

Specified by:

submitWorkUnit in interface WorkUnitServer

Parameters:

u - - The finished WorkUnit.

java.rmi.RemoteException

See Also:

WorkUnitServer.submitWorkUnit(lima.distribution.WorkUnit)

toString

public java.lang.String toString()

Produce a status string.

Overrides:

toString in class java.rmi.server.RemoteObject

See Also:

Object.toString()

main

public static void main(java.lang.String[] args)

Start up a standalone DServer.This is the normal way to create a DServer. It should be possible to run DServer in the process of the system that creates the wus. This is not as good as providing a standalone server that supports multiple clients. Note that the processing is FCFS batch.

Parameters:

args -

run

public void run()

Implementation provided for clients that require a runnable interface.

Specified by:

run in interface java.lang.Runnable

registerObserver

public void registerObserver(lima.observation.Observer observer)

Register the specified observer with an observable object.

Specified by:

registerObserver in interface Observable

unregisterObserver

public void unregisterObserver(lima.observation.Observer observer)

Unregister the specified observer with an observable object.

Specified by:

unregisterObserver in interface Observable

clearObservers

public void clearObservers()

Unregister all observers for an observable object.

Specified by:

clearObservers in interface Observable

notifyObservers

public void notifyObservers(lima.observation.Event event)

Notify all registered observers of the specified event.

Specified by:

notifyObservers in interface Observable