rice.pastry.standard
Class ConsistentJoinProtocol

java.lang.Object
  rice.pastry.client.PastryAppl
      rice.pastry.standard.StandardJoinProtocol
          rice.pastry.standard.ConsistentJoinProtocol

All Implemented Interfaces:

java.util.Observer, NodeSetListener, LoopObserver

public class ConsistentJoinProtocol
extends StandardJoinProtocol
implements java.util.Observer, NodeSetListener, LoopObserver

Does not setReady until contacting entire leafset which gossips new members. Provides consistency as long as checkLiveness() never incorrectly reports a node faulty. Based on MSR-TR-2003-94. The difference is that our assumption that checkLiveness() is much stronger because we are using DSR rather than checking ourself. Another difference is that we are unwilling to pull nodes from our leafset without checkingLiveness() ourself.

Author:

Jeff Hoye

Field Summary

protected int	MAX_NUM_TO_HEAR_FROM The number of nodes needed to hear from to go live, can be up to the LeafSet.maxSize()
protected int	MAX_TIME_TO_BE_SCHEDULED This variable is set to prevent the process from going to sleep or not being scheduled for too long.
int	RETRY_INTERVAL Will retry sending ConsistentJoinMsg to all neighbors who have not responded on this interval.
protected boolean	tryingToGoReady Suppresses sendTheMessage() if we are not ready to do this part of the join process, or we are already done.

Fields inherited from class rice.pastry.standard.StandardJoinProtocol

leafSet, localHandle, routeTable

Fields inherited from class rice.pastry.client.PastryAppl

address, deserializer, instance, logger, receiver, thePastryNode

Constructor Summary

ConsistentJoinProtocol(PastryNode ln, NodeHandle lh, RoutingTable rt, LeafSet ls, ReadyStrategy nextReadyStrategy)

ConsistentJoinProtocol(PastryNode ln, NodeHandle lh, RoutingTable rt, LeafSet ls, ReadyStrategy nextReadyStrategy, MessageDeserializer md)
Constructor takes in the usual suspects.

Method Summary

void	addToLeafSet(NodeHandle nh) Observes all NodeHandles added to LeafSet
int	delayInterest() Part of the LoopObserver interface.
void	destroy() Called when PastryNode is destroyed.
void	loopTime(int loopTime) If it took longer than the time to detect faultiness, then other nodes may believe we are faulty.
void	nodeSetUpdate(NodeSetEventSource set, NodeHandle handle, boolean added)
void	otherNodesMaySuspectFaulty(int timeNotScheduled) Call this if there is an event such that you may have not received messages for long enough for other nodes to call you faulty.
void	receiveMessage(Message msg) Handle the CJM as in the MSR-TR
void	requestFromEveryoneWeHaventHeardFrom()
void	sendTheMessage(NodeHandle nh, boolean reply) Sends a consistent join protocol message.
protected void	setReady() This is where we start out, when the StandardJoinProtocol would call setReady();
void	update(java.util.Observable arg0, java.lang.Object arg) Can be PastryNode updates, leafset updates, or nodehandle updates.
java.util.Collection	whoDoWeNeedAResponseFrom() Returns all members of the leafset that are not in gotResponse

Methods inherited from class rice.pastry.standard.StandardJoinProtocol

broadcastRows, deliverWhenNotReady, getAddress, messageForAppl

Methods inherited from class rice.pastry.client.PastryAppl

accept, connect, enrouteMessage, getLeafSet, getNodeHandle, getNodeId, getRoutingTable, isClosest, leafSetChange, notifyReady, receiveMessageInternal, receiveSocket, register, routeMsg, routeMsgDirect, routeSetChange, setDeserializer

Methods inherited from class java.lang.Object

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

Field Detail

MAX_TIME_TO_BE_SCHEDULED

protected final int MAX_TIME_TO_BE_SCHEDULED

This variable is set to prevent the process from going to sleep or not being scheduled for too long.

MAX_NUM_TO_HEAR_FROM

protected final int MAX_NUM_TO_HEAR_FROM

The number of nodes needed to hear from to go live, can be up to the LeafSet.maxSize()

See Also:

Constant Field Values

tryingToGoReady

protected boolean tryingToGoReady

Suppresses sendTheMessage() if we are not ready to do this part of the join process, or we are already done.

RETRY_INTERVAL

public final int RETRY_INTERVAL

Will retry sending ConsistentJoinMsg to all neighbors who have not responded on this interval. Only necessary if somehow the message was dropped.

Constructor Detail

ConsistentJoinProtocol

public ConsistentJoinProtocol(PastryNode ln,
                              NodeHandle lh,
                              RoutingTable rt,
                              LeafSet ls,
                              ReadyStrategy nextReadyStrategy)

ConsistentJoinProtocol

public ConsistentJoinProtocol(PastryNode ln,
                              NodeHandle lh,
                              RoutingTable rt,
                              LeafSet ls,
                              ReadyStrategy nextReadyStrategy,
                              MessageDeserializer md)

Constructor takes in the usual suspects.

Parameters:

ln -

lh -

rt -

ls -

nextReadyStrategy - if non-null, will call nextRenderStrategy.start() when complete

md -

Method Detail

setReady

protected void setReady()

This is where we start out, when the StandardJoinProtocol would call setReady();

Overrides:

setReady in class StandardJoinProtocol

addToLeafSet

public void addToLeafSet(NodeHandle nh)

Observes all NodeHandles added to LeafSet

Parameters:

nh - the nodeHandle to add

requestFromEveryoneWeHaventHeardFrom

public void requestFromEveryoneWeHaventHeardFrom()

otherNodesMaySuspectFaulty

public void otherNodesMaySuspectFaulty(int timeNotScheduled)

Call this if there is an event such that you may have not received messages for long enough for other nodes to call you faulty. This method will call PastryNode.setReady(false) which will stop delivering messages, and then via the observer pattern will call this.update(PN, FALSE) which will call setReady() which will begin the join process again.

whoDoWeNeedAResponseFrom

public java.util.Collection whoDoWeNeedAResponseFrom()

Returns all members of the leafset that are not in gotResponse

Returns:

receiveMessage

public void receiveMessage(Message msg)

Handle the CJM as in the MSR-TR

Overrides:

receiveMessage in class StandardJoinProtocol

Parameters:

msg - the message that was received.

sendTheMessage

public void sendTheMessage(NodeHandle nh,
                           boolean reply)

Sends a consistent join protocol message.

Parameters:

nh -

reply - if the reason we are sending this message is just as a response

nodeSetUpdate

public void nodeSetUpdate(NodeSetEventSource set,
                          NodeHandle handle,
                          boolean added)

Specified by:

nodeSetUpdate in interface NodeSetListener

update

public void update(java.util.Observable arg0,
                   java.lang.Object arg)

Can be PastryNode updates, leafset updates, or nodehandle updates.

Specified by:

update in interface java.util.Observer

delayInterest

public int delayInterest()

Part of the LoopObserver interface. Used to detect if we may have been found faulty by other nodes.

Specified by:

delayInterest in interface LoopObserver

Returns:

the minimum loop time we are interested in being notified about.

loopTime

public void loopTime(int loopTime)

If it took longer than the time to detect faultiness, then other nodes may believe we are faulty. So we best rejoin.

Specified by:

loopTime in interface LoopObserver

Parameters:

loopTime - the time it took to do a single selection loop.

destroy

public void destroy()

Description copied from class: PastryAppl

Called when PastryNode is destroyed. Can be overloaded by applications.

Overrides:

destroy in class PastryAppl