test/loops/MapLoops.java

/* 
 * @test
 * @synopsis Exercise multithreaded maps, by default
 * ConcurrentHashMap.  Each thread does a random walk though elements
 * of "key" array. On each iteration, it checks if table includes key.
 * If absent, with probablility pinsert it inserts it, and if present,
 * with probablility premove it removes it.  (pinsert and premove are
 * expressed as percentages to simplify parsing from command line.)
 */
/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain. Use, modify, and
 * redistribute this code in any way without acknowledgement.
 */


import java.util.*;
import java.util.concurrent.*;

public class MapLoops {
    static int nkeys       = 1000; 
    static int pinsert     = 60;
    static int premove     = 2;
    static int maxThreads  = 100;
    static int nops        = 1000000;
    static int removesPerMaxRandom;
    static int insertsPerMaxRandom;

    static final ExecutorService pool = Executors.newCachedThreadPool();

    public static void main(String[] args) throws Exception {

        Class mapClass = null;
        if (args.length > 0) {
            try {
                mapClass = Class.forName(args[0]);
            } catch(ClassNotFoundException e) {
                throw new RuntimeException("Class " + args[0] + " not found.");
            }
        }
        else 
            mapClass = java.util.concurrent.ConcurrentHashMap.class;

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

        if (args.length > 2) 
            nkeys = Integer.parseInt(args[2]);

        if (args.length > 3) 
            pinsert = Integer.parseInt(args[3]);

        if (args.length > 4) 
            premove = Integer.parseInt(args[4]);

        if (args.length > 5) 
            nops = Integer.parseInt(args[5]);

        // normalize probabilities wrt random number generator
        removesPerMaxRandom = (int)(((double)premove/100.0 * 0x7FFFFFFFL));
        insertsPerMaxRandom = (int)(((double)pinsert/100.0 * 0x7FFFFFFFL));
        
        System.out.print("Class: " + mapClass.getName());
        System.out.print(" threads: " + maxThreads);
        System.out.print(" size: " + nkeys);
        System.out.print(" ins: " + pinsert);
        System.out.print(" rem: " + premove);
        System.out.print(" ops: " + nops);
        System.out.println();

        int k = 1;
        int warmups = 2;
        for (int i = 1; i <= maxThreads;) {
            Thread.sleep(100);
            test(i, nkeys, mapClass);
            if (warmups > 0)
                --warmups;
            else if (i == k) {
                k = i << 1;
                i = i + (i >>> 1);
            } 
            else if (i == 1 && k == 2) {
                i = k;
                warmups = 1;
            }
            else 
                i = k;
        }
        pool.shutdown();
    }

    static Integer[] makeKeys(int n) {
        LoopHelpers.SimpleRandom rng = new LoopHelpers.SimpleRandom();
        Integer[] key = new Integer[n];
        for (int i = 0; i < key.length; ++i) 
            key[i] = new Integer(rng.next());
        return key;
    }

    static void shuffleKeys(Integer[] key) {
        Random rng = new Random();
        for (int i = key.length; i > 1; --i) {
            int j = rng.nextInt(i);
            Integer tmp = key[j];
            key[j] = key[i-1];
            key[i-1] = tmp;
        }
    }

    static void test(int i, int nkeys, Class mapClass) throws Exception {
        System.out.print("Threads: " + i + "\t:");
        Map<Integer, Integer> map = (Map<Integer,Integer>)mapClass.newInstance();
        Integer[] key = makeKeys(nkeys);
        // Uncomment to start with a non-empty table
        //        for (int j = 0; j < nkeys; j += 4) // start 1/4 occupied
        //            map.put(key[j], key[j]);
        shuffleKeys(key);
        LoopHelpers.BarrierTimer timer = new LoopHelpers.BarrierTimer();
        CyclicBarrier barrier = new CyclicBarrier(i+1, timer);
        for (int t = 0; t < i; ++t) 
            pool.execute(new Runner(t, map, key, barrier));
        barrier.await();
        barrier.await();
        long time = timer.getTime();
        long tpo = time / (i * (long)nops);
        System.out.print(LoopHelpers.rightJustify(tpo) + " ns per op");
        double secs = (double)(time) / 1000000000.0;
        System.out.println("\t " + secs + "s run time");
        map.clear();
    }

    static class Runner implements Runnable {
        final Map<Integer,Integer> map;
        final Integer[] key;
        final LoopHelpers.SimpleRandom rng;
        final CyclicBarrier barrier;
        int position;
        int total;

        Runner(int id, Map<Integer,Integer> map, Integer[] key,  CyclicBarrier barrier) {
            this.map = map; 
            this.key = key; 
            this.barrier = barrier;
            position = key.length / 2; 
            rng = new LoopHelpers.SimpleRandom((id + 1) * 8862213513L);
            rng.next();
        }

        int step() {
            // random-walk around key positions,  bunching accesses
            int r = rng.next();
            position += (r & 7) - 3;
            while (position >= key.length) position -= key.length;  
            while (position < 0) position += key.length;

            Integer k = key[position];
            Integer x = map.get(k);

            if (x != null) {
                if (x.intValue() != k.intValue()) 
                    throw new Error("bad mapping: " + x + " to " + k);

                if (r < removesPerMaxRandom) {
                    if (map.remove(k) != null) {
                        position = total % key.length; // move from position
                        return 2;
                    }
                }
            }
            else if (r < insertsPerMaxRandom) {
                ++position;
                map.put(k, k);
                return 2;
            } 

            // Uncomment to add a little computation between accesses
            //            total += LoopHelpers.compute1(k.intValue());
            total += r;
            return 1;
        }

        public void run() {
            try {
                barrier.await();
                int ops = nops;
                while (ops > 0) 
                    ops -= step();
                barrier.await();
            }
            catch (Exception ex) {
                ex.printStackTrace();
            }
        }
    }
}

Revision:	1.2
Committed:	Sun Aug 7 19:25:55 2005 UTC (18 years, 8 months ago) by dl
Branch:	MAIN
Changes since 1.1:	+9 -6 lines
Log Message:	Add exchanger performance tests; update others
#	Content
1	/*
2	* @test
3	* @synopsis Exercise multithreaded maps, by default
4	* ConcurrentHashMap. Each thread does a random walk though elements
5	* of "key" array. On each iteration, it checks if table includes key.
6	* If absent, with probablility pinsert it inserts it, and if present,
7	* with probablility premove it removes it. (pinsert and premove are
8	* expressed as percentages to simplify parsing from command line.)
9	*/
10	/*
11	* Written by Doug Lea with assistance from members of JCP JSR-166
12	* Expert Group and released to the public domain. Use, modify, and
13	* redistribute this code in any way without acknowledgement.
14	*/
15
16
17	import java.util.*;
18	import java.util.concurrent.*;
19
20	public class MapLoops {
21	static int nkeys = 1000;
22	static int pinsert = 60;
23	static int premove = 2;
24	static int maxThreads = 100;
25	static int nops = 1000000;
26	static int removesPerMaxRandom;
27	static int insertsPerMaxRandom;
28
29	static final ExecutorService pool = Executors.newCachedThreadPool();
30
31	public static void main(String[] args) throws Exception {
32
33	Class mapClass = null;
34	if (args.length > 0) {
35	try {
36	mapClass = Class.forName(args[0]);
37	} catch(ClassNotFoundException e) {
38	throw new RuntimeException("Class " + args[0] + " not found.");
39	}
40	}
41	else
42	mapClass = java.util.concurrent.ConcurrentHashMap.class;
43
44	if (args.length > 1)
45	maxThreads = Integer.parseInt(args[1]);
46
47	if (args.length > 2)
48	nkeys = Integer.parseInt(args[2]);
49
50	if (args.length > 3)
51	pinsert = Integer.parseInt(args[3]);
52
53	if (args.length > 4)
54	premove = Integer.parseInt(args[4]);
55
56	if (args.length > 5)
57	nops = Integer.parseInt(args[5]);
58
59	// normalize probabilities wrt random number generator
60	removesPerMaxRandom = (int)(((double)premove/100.0 * 0x7FFFFFFFL));
61	insertsPerMaxRandom = (int)(((double)pinsert/100.0 * 0x7FFFFFFFL));
62
63	System.out.print("Class: " + mapClass.getName());
64	System.out.print(" threads: " + maxThreads);
65	System.out.print(" size: " + nkeys);
66	System.out.print(" ins: " + pinsert);
67	System.out.print(" rem: " + premove);
68	System.out.print(" ops: " + nops);
69	System.out.println();
70
71	int k = 1;
72	int warmups = 2;
73	for (int i = 1; i <= maxThreads;) {
74	Thread.sleep(100);
75	test(i, nkeys, mapClass);
76	if (warmups > 0)
77	--warmups;
78	else if (i == k) {
79	k = i << 1;
80	i = i + (i >>> 1);
81	}
82	else if (i == 1 && k == 2) {
83	i = k;
84	warmups = 1;
85	}
86	else
87	i = k;
88	}
89	pool.shutdown();
90	}
91
92	static Integer[] makeKeys(int n) {
93	LoopHelpers.SimpleRandom rng = new LoopHelpers.SimpleRandom();
94	Integer[] key = new Integer[n];
95	for (int i = 0; i < key.length; ++i)
96	key[i] = new Integer(rng.next());
97	return key;
98	}
99
100	static void shuffleKeys(Integer[] key) {
101	Random rng = new Random();
102	for (int i = key.length; i > 1; --i) {
103	int j = rng.nextInt(i);
104	Integer tmp = key[j];
105	key[j] = key[i-1];
106	key[i-1] = tmp;
107	}
108	}
109
110	static void test(int i, int nkeys, Class mapClass) throws Exception {
111	System.out.print("Threads: " + i + "\t:");
112	Map<Integer, Integer> map = (Map<Integer,Integer>)mapClass.newInstance();
113	Integer[] key = makeKeys(nkeys);
114	// Uncomment to start with a non-empty table
115	// for (int j = 0; j < nkeys; j += 4) // start 1/4 occupied
116	// map.put(key[j], key[j]);
117	shuffleKeys(key);
118	LoopHelpers.BarrierTimer timer = new LoopHelpers.BarrierTimer();
119	CyclicBarrier barrier = new CyclicBarrier(i+1, timer);
120	for (int t = 0; t < i; ++t)
121	pool.execute(new Runner(t, map, key, barrier));
122	barrier.await();
123	barrier.await();
124	long time = timer.getTime();
125	long tpo = time / (i * (long)nops);
126	System.out.print(LoopHelpers.rightJustify(tpo) + " ns per op");
127	double secs = (double)(time) / 1000000000.0;
128	System.out.println("\t " + secs + "s run time");
129	map.clear();
130	}
131
132	static class Runner implements Runnable {
133	final Map<Integer,Integer> map;
134	final Integer[] key;
135	final LoopHelpers.SimpleRandom rng;
136	final CyclicBarrier barrier;
137	int position;
138	int total;
139
140	Runner(int id, Map<Integer,Integer> map, Integer[] key, CyclicBarrier barrier) {
141	this.map = map;
142	this.key = key;
143	this.barrier = barrier;
144	position = key.length / 2;
145	rng = new LoopHelpers.SimpleRandom((id + 1) * 8862213513L);
146	rng.next();
147	}
148
149	int step() {
150	// random-walk around key positions, bunching accesses
151	int r = rng.next();
152	position += (r & 7) - 3;
153	while (position >= key.length) position -= key.length;
154	while (position < 0) position += key.length;
155
156	Integer k = key[position];
157	Integer x = map.get(k);
158
159	if (x != null) {
160	if (x.intValue() != k.intValue())
161	throw new Error("bad mapping: " + x + " to " + k);
162
163	if (r < removesPerMaxRandom) {
164	if (map.remove(k) != null) {
165	position = total % key.length; // move from position
166	return 2;
167	}
168	}
169	}
170	else if (r < insertsPerMaxRandom) {
171	++position;
172	map.put(k, k);
173	return 2;
174	}
175
176	// Uncomment to add a little computation between accesses
177	// total += LoopHelpers.compute1(k.intValue());
178	total += r;
179	return 1;
180	}
181
182	public void run() {
183	try {
184	barrier.await();
185	int ops = nops;
186	while (ops > 0)
187	ops -= step();
188	barrier.await();
189	}
190	catch (Exception ex) {
191	ex.printStackTrace();
192	}
193	}
194	}
195	}
196