package org.jgroups.tests;
import org.jgroups.Address;
import org.jgroups.Message;
import org.jgroups.stack.NakReceiverWindow;
import org.jgroups.stack.Retransmitter;
import org.jgroups.util.DefaultTimeScheduler;
import org.jgroups.util.TimeScheduler;
import org.jgroups.util.Util;
import java.io.IOException;
/**
* Adds a large number of messages (with gaps to simulate message loss) into NakReceiverWindow. Receives messages
* on another thread. When the receiver thread has received all messages it prints out the time taken and terminates.
*
* @author Bela Ban
*/
public class NakReceiverWindowStressTest implements Retransmitter.RetransmitCommand {
NakReceiverWindow win=null;
final Address sender=Util.createRandomAddress("A");
int num_msgs=1000, prev_value=0;
double discard_prob=0.0; // discard 0% of all insertions
long start, stop;
boolean trace=false;
boolean debug=false;
public NakReceiverWindowStressTest(int num_msgs, double discard_prob, boolean trace) {
this.num_msgs=num_msgs;
this.discard_prob=discard_prob;
this.trace=trace;
}
public void retransmit(long first_seqno, long last_seqno, Address sender) {
for(long i=first_seqno; i <= last_seqno; i++) {
if(debug)
out("-- xmit: " + i);
Message m=new Message(null, sender, new Long(i));
win.add(i, m);
}
}
public void start() throws IOException, InterruptedException {
System.out.println("num_msgs=" + num_msgs + "\ndiscard_prob=" + discard_prob);
TimeScheduler timer=new DefaultTimeScheduler();
try {
win=new NakReceiverWindow(sender, this, 0, timer);
start=System.currentTimeMillis();
sendMessages(num_msgs);
}
finally {
timer.stop();
}
}
void sendMessages(int num_msgs) {
Message msg;
for(long i=1; i <= num_msgs; i++) {
if(discard_prob > 0 && Util.tossWeightedCoin(discard_prob) && i <= num_msgs) {
if(debug) out("-- discarding " + i);
}
else {
if(debug) out("-- adding " + i);
win.add(i, new Message(null, null, new Long(i)));
if(trace && i % 1000 == 0)
System.out.println("-- added " + i);
while((msg=win.remove()) != null)
processMessage(msg);
}
}
while(true) {
while((msg=win.remove()) != null)
processMessage(msg);
}
}
void processMessage(Message msg) {
long i;
i=((Long)msg.getObject()).longValue();
if(prev_value + 1 != i) {
System.err.println("** processMessage(): removed seqno (" + i + ") is not 1 greater than " +
"previous value (" + prev_value + ')');
System.exit(0);
}
prev_value++;
if(trace && i % 1000 == 0)
System.out.println("Removed " + i);
if(i == num_msgs) {
stop=System.currentTimeMillis();
long total=stop-start;
double msgs_per_sec=num_msgs / (total/1000.0);
double msgs_per_ms=num_msgs / (double)total;
System.out.println("Inserting and removing " + num_msgs +
" messages into NakReceiverWindow took " + total + "ms");
System.out.println("Msgs/sec: " + msgs_per_sec + ", msgs/ms: " + msgs_per_ms);
System.out.println("<enter> to terminate");
try {
System.in.read();
}
catch(Exception ex) {
System.err.println(ex);
}
System.exit(0);
}
}
static void out(String msg) {
System.out.println(msg);
}
public static void main(String[] args) {
NakReceiverWindowStressTest test;
int num_msgs=1000;
double discard_prob=0.0;
boolean trace=false;
for(int i=0; i < args.length; i++) {
if("-help".equals(args[i])) {
help();
return;
}
if("-num_msgs".equals(args[i])) {
num_msgs=Integer.parseInt(args[++i]);
continue;
}
if("-discard".equals(args[i])) {
discard_prob=Double.parseDouble(args[++i]);
continue;
}
if("-trace".equals(args[i])) {
trace=true;
}
}
test=new NakReceiverWindowStressTest(num_msgs, discard_prob, trace);
try {
test.start();
}
catch(IOException e) {
e.printStackTrace();
}
catch(InterruptedException e) {
e.printStackTrace();
}
}
static void help() {
System.out.println("NakReceiverWindowStressTest [-help] [-num_msgs <number>] [-discard <probability>] " +
"[-trace]");
}
}