test/loops/ConcurrentDequeLoops.java

/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 */

import java.util.ArrayList;
import java.util.Deque;
import java.util.concurrent.Callable;
import java.util.concurrent.CyclicBarrier;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.atomic.AtomicInteger;

public class ConcurrentDequeLoops {
    static final ExecutorService pool = Executors.newCachedThreadPool();
    static AtomicInteger totalItems;
    static boolean print = false;

    public static void main(String[] args) throws Exception {
        int maxStages = 8;
        int items = 1000000;

        Class<?> klass = null;
        if (args.length > 0) {
            try {
                klass = Class.forName(args[0]);
            } catch (ClassNotFoundException e) {
                throw new RuntimeException("Class " + args[0] + " not found.");
            }
        }
        else
            throw new Error();

        if (args.length > 1)
            maxStages = Integer.parseInt(args[1]);

        System.out.print("Class: " + klass.getName());
        System.out.println(" stages: " + maxStages);

        print = false;
        System.out.println("Warmup...");
        oneRun(klass, 1, items);
        Thread.sleep(100);
        oneRun(klass, 1, items);
        Thread.sleep(100);
        print = true;

        for (int k = 1, i = 1; i <= maxStages;) {
            oneRun(klass, i, items);
            if (i == k) {
                k = i << 1;
                i = i + (i >>> 1);
            }
            else
                i = k;
        }
        pool.shutdown();
    }

    static class Stage implements Callable<Integer> {
        final Deque<Integer> queue;
        final CyclicBarrier barrier;
        final LoopHelpers.SimpleRandom rng = new LoopHelpers.SimpleRandom();
        int items;
        Stage(Deque<Integer> q, CyclicBarrier b, int items) {
            queue = q;
            barrier = b;
            this.items = items;
        }

        public Integer call() {
            // Repeatedly take something from queue if possible,
            // transform it, and put back in.
            try {
                barrier.await();
                int l = (int) System.nanoTime();
                int takes = 0;
                for (;;) {
                    Integer item;
                    int rnd = rng.next();
                    if ((rnd & 1) == 0)
                        item = queue.pollFirst();
                    else
                        item = queue.pollLast();
                    if (item != null) {
                        ++takes;
                        l += LoopHelpers.compute2(item.intValue());
                    }
                    else if (takes != 0) {
                        totalItems.getAndAdd(-takes);
                        takes = 0;
                    }
                    else if (totalItems.get() <= 0)
                        break;
                    l = LoopHelpers.compute1(l);
                    if (items > 0) {
                        --items;
                        Integer res = new Integer(l);
                        if ((rnd & 16) == 0)
                            queue.addFirst(res);
                        else
                            queue.addLast(res);
                    }
                    else { // spinwait
                        for (int k = 1 + (l & 15); k != 0; --k)
                            l = LoopHelpers.compute1(LoopHelpers.compute2(l));
                        if ((l & 3) == 3) {
                            Thread.sleep(1);
                        }
                    }
                }
                return new Integer(l);
            }
            catch (Exception ie) {
                ie.printStackTrace();
                throw new Error("Call loop failed");
            }
        }
    }

    static void oneRun(Class<?> klass, int n, int items) throws Exception {
        Deque<Integer> q =
            (Deque<Integer>) klass.getConstructor().newInstance();
        LoopHelpers.BarrierTimer timer = new LoopHelpers.BarrierTimer();
        CyclicBarrier barrier = new CyclicBarrier(n + 1, timer);
        totalItems = new AtomicInteger(n * items);
        ArrayList<Future<Integer>> results = new ArrayList<Future<Integer>>(n);
        for (int i = 0; i < n; ++i)
            results.add(pool.submit(new Stage(q, barrier, items)));

        if (print)
            System.out.print("Threads: " + n + "\t:");
        barrier.await();
        int total = 0;
        for (int i = 0; i < n; ++i) {
            Future<Integer> f = results.get(i);
            Integer r = f.get();
            total += r.intValue();
        }
        long endTime = System.nanoTime();
        long time = endTime - timer.startTime;
        if (print)
            System.out.println(LoopHelpers.rightJustify(time / (items * n)) + " ns per item");
        if (total == 0) // avoid overoptimization
            System.out.println("useless result: " + total);
    }
}
Revision:	1.14
Committed:	Sat Dec 31 19:02:43 2016 UTC (7 years, 3 months ago) by jsr166
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.13:	+8 -4 lines
Log Message:	organize imports
#	Content
1	/*
2	* Written by Doug Lea with assistance from members of JCP JSR-166
3	* Expert Group and released to the public domain, as explained at
4	* http://creativecommons.org/publicdomain/zero/1.0/
5	*/
6
7	import java.util.ArrayList;
8	import java.util.Deque;
9	import java.util.concurrent.Callable;
10	import java.util.concurrent.CyclicBarrier;
11	import java.util.concurrent.ExecutorService;
12	import java.util.concurrent.Executors;
13	import java.util.concurrent.Future;
14	import java.util.concurrent.atomic.AtomicInteger;
15
16	public class ConcurrentDequeLoops {
17	static final ExecutorService pool = Executors.newCachedThreadPool();
18	static AtomicInteger totalItems;
19	static boolean print = false;
20
21	public static void main(String[] args) throws Exception {
22	int maxStages = 8;
23	int items = 1000000;
24
25	Class<?> klass = null;
26	if (args.length > 0) {
27	try {
28	klass = Class.forName(args[0]);
29	} catch (ClassNotFoundException e) {
30	throw new RuntimeException("Class " + args[0] + " not found.");
31	}
32	}
33	else
34	throw new Error();
35
36	if (args.length > 1)
37	maxStages = Integer.parseInt(args[1]);
38
39	System.out.print("Class: " + klass.getName());
40	System.out.println(" stages: " + maxStages);
41
42	print = false;
43	System.out.println("Warmup...");
44	oneRun(klass, 1, items);
45	Thread.sleep(100);
46	oneRun(klass, 1, items);
47	Thread.sleep(100);
48	print = true;
49
50	for (int k = 1, i = 1; i <= maxStages;) {
51	oneRun(klass, i, items);
52	if (i == k) {
53	k = i << 1;
54	i = i + (i >>> 1);
55	}
56	else
57	i = k;
58	}
59	pool.shutdown();
60	}
61
62	static class Stage implements Callable<Integer> {
63	final Deque<Integer> queue;
64	final CyclicBarrier barrier;
65	final LoopHelpers.SimpleRandom rng = new LoopHelpers.SimpleRandom();
66	int items;
67	Stage(Deque<Integer> q, CyclicBarrier b, int items) {
68	queue = q;
69	barrier = b;
70	this.items = items;
71	}
72
73	public Integer call() {
74	// Repeatedly take something from queue if possible,
75	// transform it, and put back in.
76	try {
77	barrier.await();
78	int l = (int) System.nanoTime();
79	int takes = 0;
80	for (;;) {
81	Integer item;
82	int rnd = rng.next();
83	if ((rnd & 1) == 0)
84	item = queue.pollFirst();
85	else
86	item = queue.pollLast();
87	if (item != null) {
88	++takes;
89	l += LoopHelpers.compute2(item.intValue());
90	}
91	else if (takes != 0) {
92	totalItems.getAndAdd(-takes);
93	takes = 0;
94	}
95	else if (totalItems.get() <= 0)
96	break;
97	l = LoopHelpers.compute1(l);
98	if (items > 0) {
99	--items;
100	Integer res = new Integer(l);
101	if ((rnd & 16) == 0)
102	queue.addFirst(res);
103	else
104	queue.addLast(res);
105	}
106	else { // spinwait
107	for (int k = 1 + (l & 15); k != 0; --k)
108	l = LoopHelpers.compute1(LoopHelpers.compute2(l));
109	if ((l & 3) == 3) {
110	Thread.sleep(1);
111	}
112	}
113	}
114	return new Integer(l);
115	}
116	catch (Exception ie) {
117	ie.printStackTrace();
118	throw new Error("Call loop failed");
119	}
120	}
121	}
122
123	static void oneRun(Class<?> klass, int n, int items) throws Exception {
124	Deque<Integer> q =
125	(Deque<Integer>) klass.getConstructor().newInstance();
126	LoopHelpers.BarrierTimer timer = new LoopHelpers.BarrierTimer();
127	CyclicBarrier barrier = new CyclicBarrier(n + 1, timer);
128	totalItems = new AtomicInteger(n * items);
129	ArrayList<Future<Integer>> results = new ArrayList<Future<Integer>>(n);
130	for (int i = 0; i < n; ++i)
131	results.add(pool.submit(new Stage(q, barrier, items)));
132
133	if (print)
134	System.out.print("Threads: " + n + "\t:");
135	barrier.await();
136	int total = 0;
137	for (int i = 0; i < n; ++i) {
138	Future<Integer> f = results.get(i);
139	Integer r = f.get();
140	total += r.intValue();
141	}
142	long endTime = System.nanoTime();
143	long time = endTime - timer.startTime;
144	if (print)
145	System.out.println(LoopHelpers.rightJustify(time / (items * n)) + " ns per item");
146	if (total == 0) // avoid overoptimization
147	System.out.println("useless result: " + total);
148	}
149	}