package org.infinispan.demo.distexec;
import com.martiansoftware.jsap.FlaggedOption;
import com.martiansoftware.jsap.JSAP;
import com.martiansoftware.jsap.JSAPException;
import com.martiansoftware.jsap.Parameter;
import com.martiansoftware.jsap.SimpleJSAP;
import org.infinispan.Cache;
import org.infinispan.demo.Demo;
import org.infinispan.distexec.DefaultExecutorService;
import org.infinispan.distexec.DistributedExecutorService;
import org.infinispan.util.Util;
import java.io.Serializable;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.Future;
import java.util.concurrent.locks.LockSupport;
/**
* Infinispan distributed executors demo using pi approximation.
*/
public class PiApproximationDemo extends Demo {
private static final int DEFAULT_NUM_POINTS = 50000000;
private int numPoints;
public static void main(String... args) throws Exception {
new PiApproximationDemo(args).run();
}
public PiApproximationDemo(String[] args) throws Exception {
super(args);
numPoints = commandLineOptions.getInt("numPoints");
}
public void run() throws Exception {
// Step 1: start cache.
Cache<String, String> cache = startCache();
// Step 2: run Pi Approximation
try {
if (isMaster) {
int numServers = cache.getCacheManager().getMembers().size();
int numberPerWorker = numPoints / numServers;
DistributedExecutorService des = new DefaultExecutorService(cache);
long start = System.currentTimeMillis();
List<Future<Integer>> results = des.submitEverywhere(new CircleTest(numberPerWorker));
int insideCircleCount = 0;
for (Future<Integer> f : results) insideCircleCount += f.get();
double appxPi = 4.0 * insideCircleCount / numPoints;
System.out.printf("Pi approximation is %s, computed in %s using %s nodes.%n", appxPi, Util.prettyPrintTime(System.currentTimeMillis() - start), numServers);
} else {
System.out.println("Slave node waiting for Map/Reduce tasks. Ctrl-C to exit.");
LockSupport.park();
}
} finally {
cache.getCacheManager().stop();
}
}
private static class CircleTest implements Callable<Integer>, Serializable {
/**
* The serialVersionUID
*/
private static final long serialVersionUID = 3496135215525904755L;
private final int loopCount;
public CircleTest(int loopCount) {
this.loopCount = loopCount;
}
@Override
public Integer call() throws Exception {
int insideCircleCount = 0;
for (int i = 0; i < loopCount; i++) {
double x = Math.random();
double y = Math.random();
if (insideCircle(x, y))
insideCircleCount++;
}
return insideCircleCount;
}
private boolean insideCircle(double x, double y) {
return (Math.pow(x - 0.5, 2) + Math.pow(y - 0.5, 2)) <= Math.pow(0.5, 2);
}
}
@Override
protected SimpleJSAP buildCommandLineOptions() throws JSAPException {
return new SimpleJSAP("PiApproximationDemo",
"Approximate Pi using Infinispan DistributedExecutorService ", new Parameter[]{
new FlaggedOption("configFile", JSAP.STRING_PARSER, "config-samples/distributed-udp.xml",
JSAP.NOT_REQUIRED, 'c', "configFile",
"Infinispan config file"),
new FlaggedOption("nodeType", JSAP.STRING_PARSER, "slave", JSAP.REQUIRED,
't', "nodeType", "Node type as either master or slave"),
new FlaggedOption("numPoints", JSAP.INTEGER_PARSER,
String.valueOf(DEFAULT_NUM_POINTS), JSAP.REQUIRED, 'n',
"numPoints", "Total number of darts to shoot"),
});
}
}