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
#	User	Rev	Content
1	dl	1.1	/*
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	dl	1.2	static int nkeys = 1000;
22	dl	1.1	static int pinsert = 60;
23			static int premove = 2;
24			static int maxThreads = 100;
25	dl	1.2	static int nops = 1000000;
26	dl	1.1	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	dl	1.2	shuffleKeys(key);
118	dl	1.1	LoopHelpers.BarrierTimer timer = new LoopHelpers.BarrierTimer();
119			CyclicBarrier barrier = new CyclicBarrier(i+1, timer);
120			for (int t = 0; t < i; ++t)
121	dl	1.2	pool.execute(new Runner(t, map, key, barrier));
122	dl	1.1	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	dl	1.2	final LoopHelpers.SimpleRandom rng;
136	dl	1.1	final CyclicBarrier barrier;
137			int position;
138			int total;
139
140	dl	1.2	Runner(int id, Map<Integer,Integer> map, Integer[] key, CyclicBarrier barrier) {
141	dl	1.1	this.map = map;
142			this.key = key;
143			this.barrier = barrier;
144	dl	1.2	position = key.length / 2;
145			rng = new LoopHelpers.SimpleRandom((id + 1) * 8862213513L);
146			rng.next();
147	dl	1.1	}
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