org.jgroups.protocols

Class FD_PROB

public class FD_PROB extends Protocol implements Runnable

Probabilistic failure detection protocol based on "A Gossip-Style Failure Detection Service" by Renesse, Minsky and Hayden.

Each member maintains a list of all other members: for each member P, 2 data are maintained, a heartbeat counter and the time of the last increment of the counter. Each member periodically sends its own heartbeat counter list to a randomly chosen member Q. Q updates its own heartbeat counter list and the associated time (if counter was incremented). Each member periodically increments its own counter. If, when sending its heartbeat counter list, a member P detects that another member Q's heartbeat counter was not incremented for timeout seconds, Q will be suspected.

This protocol can be used both with a PBCAST *and* regular stacks.

Version: $Revision: 1.9 $

Author: Bela Ban 1999

Nested Class Summary
static classFD_PROB.FdHeader
Method Summary
voiddown(Event evt)
StringgetName()
voidrun()
Loop while more than 1 member available.
booleansetProperties(Properties props)
voidstart()
voidstop()
voidup(Event evt)

Method Detail

down

public void down(Event evt)

getName

public String getName()

run

public void run()
Loop while more than 1 member available. Choose a member randomly (not myself !) and send a heartbeat. Wait for ack. If ack not received withing timeout, mcast SUSPECT message.

setProperties

public boolean setProperties(Properties props)

start

public void start()

stop

public void stop()

up

public void up(Event evt)
Copyright ? 1998-2005 Bela Ban. All Rights Reserved.