util/Collection/RemoveMicroBenchmark.java

/*
 * Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * @test
 * @summary micro-benchmark correctness mode
 * @run main RemoveMicroBenchmark iterations=1 size=8 warmup=0
 */

import static java.util.stream.Collectors.toCollection;

import java.lang.ref.WeakReference;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Deque;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.ListIterator;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Vector;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingDeque;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ConcurrentLinkedDeque;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.LinkedTransferQueue;
import java.util.concurrent.PriorityBlockingQueue;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;
import java.util.regex.Pattern;
import java.util.stream.Stream;

/**
 * Usage: [iterations=N] [size=N] [filter=REGEXP] [warmup=SECONDS]
 *
 * To run this in micro-benchmark mode, simply run as a normal java program.
 * Be patient; this program runs for a very long time.
 * For faster runs, restrict execution using command line args.
 *
 * @author Martin Buchholz
 */
public class RemoveMicroBenchmark {
    abstract static class Job {
        private final String name;
        public Job(String name) { this.name = name; }
        public String name() { return name; }
        public abstract void work() throws Throwable;
        public void run() {
            try { work(); }
            catch (Throwable ex) {
                // current job cannot always be deduced from stacktrace.
                throw new RuntimeException("Job failed: " + name(), ex);
            }
        }
    }

    final int iterations;
    final int size;             // number of elements in collections
    final double warmupSeconds;
    final long warmupNanos;
    final Pattern nameFilter;   // select subset of Jobs to run
    final boolean reverse;      // reverse order of Jobs
    final boolean shuffle;      // randomize order of Jobs

    final ArrayList<Integer> elements; // contains size random Integers

    RemoveMicroBenchmark(String[] args) {
        iterations    = intArg(args, "iterations", 10_000);
        size          = intArg(args, "size", 1000);
        warmupSeconds = doubleArg(args, "warmup", 7.0);
        nameFilter    = patternArg(args, "filter");
        reverse       = booleanArg(args, "reverse");
        shuffle       = booleanArg(args, "shuffle");

        warmupNanos = (long) (warmupSeconds * (1000L * 1000L * 1000L));

        elements = ThreadLocalRandom.current().ints(size)
            .mapToObj(x -> x)
            .collect(toCollection(ArrayList::new));
    }

    // --------------- GC finalization infrastructure ---------------

    /** No guarantees, but effective in practice. */
    static void forceFullGc() {
        CountDownLatch finalizeDone = new CountDownLatch(1);
        WeakReference<?> ref = new WeakReference<Object>(new Object() {
            @SuppressWarnings("deprecation")
            protected void finalize() { finalizeDone.countDown(); }});
        try {
            for (int i = 0; i < 10; i++) {
                System.gc();
                if (finalizeDone.await(1L, TimeUnit.SECONDS) && ref.get() == null) {
                    System.runFinalization(); // try to pick up stragglers
                    return;
                }
            }
        } catch (InterruptedException unexpected) {
            throw new AssertionError("unexpected InterruptedException");
        }
        throw new AssertionError("failed to do a \"full\" gc");
    }

    /**
     * Runs each job for long enough that all the runtime compilers
     * have had plenty of time to warm up, i.e. get around to
     * compiling everything worth compiling.
     * Returns array of average times per job per run.
     */
    long[] time0(List<Job> jobs) {
        final int size = jobs.size();
        long[] nanoss = new long[size];
        for (int i = 0; i < size; i++) {
            if (warmupNanos > 0) forceFullGc();
            Job job = jobs.get(i);
            long totalTime;
            int runs = 0;
            long startTime = System.nanoTime();
            do { job.run(); runs++; }
            while ((totalTime = System.nanoTime() - startTime) < warmupNanos);
            nanoss[i] = totalTime/runs;
        }
        return nanoss;
    }

    void time(List<Job> jobs) throws Throwable {
        if (warmupNanos > 0) time0(jobs); // Warm up run
        final int size = jobs.size();
        final long[] nanoss = time0(jobs); // Real timing run
        final long[] milliss = new long[size];
        final double[] ratios = new double[size];

        final String nameHeader   = "Method";
        final String millisHeader = "Millis";
        final String ratioHeader  = "Ratio";

        int nameWidth   = nameHeader.length();
        int millisWidth = millisHeader.length();
        int ratioWidth  = ratioHeader.length();

        for (int i = 0; i < size; i++) {
            nameWidth = Math.max(nameWidth, jobs.get(i).name().length());

            milliss[i] = nanoss[i]/(1000L * 1000L);
            millisWidth = Math.max(millisWidth,
                                   String.format("%d", milliss[i]).length());

            ratios[i] = (double) nanoss[i] / (double) nanoss[0];
            ratioWidth = Math.max(ratioWidth,
                                  String.format("%.3f", ratios[i]).length());
        }

        String format = String.format("%%-%ds %%%dd %%%d.3f%%n",
                                      nameWidth, millisWidth, ratioWidth);
        String headerFormat = String.format("%%-%ds %%%ds %%%ds%%n",
                                            nameWidth, millisWidth, ratioWidth);
        System.out.printf(headerFormat, "Method", "Millis", "Ratio");

        // Print out absolute and relative times, calibrated against first job
        for (int i = 0; i < size; i++)
            System.out.printf(format, jobs.get(i).name(), milliss[i], ratios[i]);
    }

    private static String keywordValue(String[] args, String keyword) {
        for (String arg : args)
            if (arg.startsWith(keyword))
                return arg.substring(keyword.length() + 1);
        return null;
    }

    private static int intArg(String[] args, String keyword, int defaultValue) {
        String val = keywordValue(args, keyword);
        return (val == null) ? defaultValue : Integer.parseInt(val);
    }

    private static double doubleArg(String[] args, String keyword, double defaultValue) {
        String val = keywordValue(args, keyword);
        return (val == null) ? defaultValue : Double.parseDouble(val);
    }

    private static Pattern patternArg(String[] args, String keyword) {
        String val = keywordValue(args, keyword);
        return (val == null) ? null : Pattern.compile(val);
    }

    private static boolean booleanArg(String[] args, String keyword) {
        String val = keywordValue(args, keyword);
        if (val == null || val.equals("false")) return false;
        if (val.equals("true")) return true;
        throw new IllegalArgumentException(val);
    }

    private static void deoptimize(int sum) {
        if (sum == 42)
            System.out.println("the answer");
    }

    private static <T> Iterable<T> backwards(final List<T> list) {
        return new Iterable<T>() {
            public Iterator<T> iterator() {
                return new Iterator<T>() {
                    final ListIterator<T> it = list.listIterator(list.size());
                    public boolean hasNext() { return it.hasPrevious(); }
                    public T next()          { return it.previous(); }
                    public void remove()     {        it.remove(); }};}};
    }

    // Checks for correctness *and* prevents loop optimizations
    static class Check {
        private int sum;
        public void sum(int sum) {
            if (this.sum == 0)
                this.sum = sum;
            if (this.sum != sum)
                throw new AssertionError("Sum mismatch");
        }
    }
    volatile Check check = new Check();

    public static void main(String[] args) throws Throwable {
        new RemoveMicroBenchmark(args).run();
    }

    HashMap<Class<?>, String> goodClassName = new HashMap<>();

    String goodClassName(Class<?> klazz) {
        return goodClassName.computeIfAbsent(
            klazz,
            k -> {
                String simple = k.getSimpleName();
                return (simple.equals("SubList")) // too simple!
                    ? k.getName().replaceFirst(".*\\.", "")
                    : simple;
            });
    }

    static List<Integer> makeSubList(List<Integer> list) {
        final ThreadLocalRandom rnd = ThreadLocalRandom.current();
        int size = rnd.nextInt(4);
        for (int i = size; i--> 0; )
            list.add(rnd.nextInt());
        int index = rnd.nextInt(size + 1);
        return list.subList(index, index);
    }

    private static <T> List<T> asSubList(List<T> list) {
        return list.subList(0, list.size());
    }

    @SafeVarargs @SuppressWarnings("varargs")
    private <T> Stream<T> concatStreams(Stream<T> ... streams) {
        return Stream.of(streams).flatMap(s -> s);
    }

    Class<?> topLevelClass(Object x) {
        for (Class<?> k = x.getClass();; ) {
            Class<?> enclosing = k.getEnclosingClass();
            if (enclosing == null)
                return k;
            k = enclosing;
        }
    }

    void run() throws Throwable {
        ArrayList<Job> jobs = Stream.<Collection<Integer>>of(
                new ArrayList<>(),
                makeSubList(new ArrayList<>()),
                new LinkedList<>(),
                makeSubList(new LinkedList<>()),
                new Vector<>(),
                makeSubList(new Vector<>()),
                new CopyOnWriteArrayList<>(),
                makeSubList(new CopyOnWriteArrayList<>()),
                new ArrayDeque<>(),
                new PriorityQueue<>(),
                new ArrayBlockingQueue<>(elements.size()),
                new ConcurrentLinkedQueue<>(),
                new ConcurrentLinkedDeque<>(),
                new LinkedBlockingQueue<>(),
                new LinkedBlockingDeque<>(),
                new LinkedTransferQueue<>(),
                new PriorityBlockingQueue<>())
            .flatMap(x -> jobs(x))
            .filter(job ->
                nameFilter == null || nameFilter.matcher(job.name()).find())
            .collect(toCollection(ArrayList::new));

        if (reverse) Collections.reverse(jobs);
        if (shuffle) Collections.shuffle(jobs);

        time(jobs);
    }

    Stream<Job> jobs(Collection<Integer> x) {
        return concatStreams(
            collectionJobs(x),

            (CopyOnWriteArrayList.class.isAssignableFrom(topLevelClass(x)))
            ? Stream.empty()
            : iteratorRemoveJobs(x),

            (x instanceof Queue)
            ? queueJobs((Queue<Integer>)x)
            : Stream.empty(),

            (x instanceof Deque)
            ? dequeJobs((Deque<Integer>)x)
            : Stream.empty(),

            (x instanceof BlockingQueue)
            ? blockingQueueJobs((BlockingQueue<Integer>)x)
            : Stream.empty(),

            (x instanceof BlockingDeque)
            ? blockingDequeJobs((BlockingDeque<Integer>)x)
            : Stream.empty());
    }

    Collection<Integer> universeRecorder(int[] sum) {
        return new ArrayList<>() {
            public boolean contains(Object x) {
                sum[0] += (Integer) x;
                return true;
            }};
    }

    Collection<Integer> emptyRecorder(int[] sum) {
        return new ArrayList<>() {
            public boolean contains(Object x) {
                sum[0] += (Integer) x;
                return false;
            }};
    }

    Stream<Job> collectionJobs(Collection<Integer> x) {
        final String klazz = goodClassName(x.getClass());
        return Stream.of(
            new Job(klazz + " removeIf") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        x.removeIf(n -> { sum[0] += n; return true; });
                        check.sum(sum[0]);}}},
            new Job(klazz + " removeIf rnd-two-pass") {
                public void work() throws Throwable {
                    ThreadLocalRandom rnd = ThreadLocalRandom.current();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        x.removeIf(n -> {
                            boolean b = rnd.nextBoolean();
                            if (b) sum[0] += n;
                            return b; });
                        x.removeIf(n -> { sum[0] += n; return true; });
                        check.sum(sum[0]);}}},
            new Job(klazz + " removeAll") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    Collection<Integer> universe = universeRecorder(sum);
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        x.removeAll(universe);
                        check.sum(sum[0]);}}},
            new Job(klazz + " retainAll") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    Collection<Integer> empty = emptyRecorder(sum);
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        x.retainAll(empty);
                        check.sum(sum[0]);}}},
            new Job(klazz + " clear") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        x.forEach(e -> sum[0] += e);
                        x.clear();
                        check.sum(sum[0]);}}});
    }

    Stream<Job> iteratorRemoveJobs(Collection<Integer> x) {
        final String klazz = goodClassName(x.getClass());
        return Stream.of(
             new Job(klazz + " Iterator.remove") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        Iterator<Integer> it = x.iterator();
                        while (it.hasNext()) {
                            sum[0] += it.next();
                            it.remove();
                        }
                        check.sum(sum[0]);}}},
            new Job(klazz + " Iterator.remove-rnd-two-pass") {
                public void work() throws Throwable {
                    ThreadLocalRandom rnd = ThreadLocalRandom.current();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        for (Iterator<Integer> it = x.iterator();
                             it.hasNext(); ) {
                            Integer e = it.next();
                            if (rnd.nextBoolean()) {
                                sum[0] += e;
                                it.remove();
                            }
                        }
                        for (Iterator<Integer> it = x.iterator();
                             it.hasNext(); ) {
                            sum[0] += it.next();
                            it.remove();
                        }
                        check.sum(sum[0]);}}});
    }

    Stream<Job> queueJobs(Queue<Integer> x) {
        final String klazz = goodClassName(x.getClass());
        return Stream.of(
            new Job(klazz + " poll()") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        for (Integer e; (e = x.poll()) != null; )
                            sum[0] += e;
                        check.sum(sum[0]);}}});
    }

    Stream<Job> dequeJobs(Deque<Integer> x) {
        final String klazz = goodClassName(x.getClass());
        return Stream.of(
            new Job(klazz + " descendingIterator().remove") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        Iterator<Integer> it = x.descendingIterator();
                        while (it.hasNext()) {
                            sum[0] += it.next();
                            it.remove();
                        }
                        check.sum(sum[0]);}}},
            new Job(klazz + " pollFirst()") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        for (Integer e; (e = x.pollFirst()) != null; )
                            sum[0] += e;
                        check.sum(sum[0]);}}},
            new Job(klazz + " pollLast()") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        for (Integer e; (e = x.pollLast()) != null; )
                            sum[0] += e;
                        check.sum(sum[0]);}}});
    }

    Stream<Job> blockingQueueJobs(BlockingQueue<Integer> x) {
        final String klazz = goodClassName(x.getClass());
        return Stream.of(
            new Job(klazz + " timed poll()") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        for (Integer e; (e = x.poll(0L, TimeUnit.DAYS)) != null; )
                            sum[0] += e;
                        check.sum(sum[0]);}}},
            new Job(klazz + " drainTo(sink)") {
                public void work() throws Throwable {
                    ArrayList<Integer> sink = new ArrayList<>();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        sink.clear();
                        x.addAll(elements);
                        x.drainTo(sink);
                        sink.forEach(e -> sum[0] += e);
                        check.sum(sum[0]);}}},
            new Job(klazz + " drainTo(sink, n)") {
                public void work() throws Throwable {
                    ArrayList<Integer> sink = new ArrayList<>();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        sink.clear();
                        x.addAll(elements);
                        x.drainTo(sink, elements.size());
                        sink.forEach(e -> sum[0] += e);
                        check.sum(sum[0]);}}});
    }

    Stream<Job> blockingDequeJobs(BlockingDeque<Integer> x) {
        final String klazz = goodClassName(x.getClass());
        return Stream.of(
            new Job(klazz + " timed pollFirst()") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        for (Integer e; (e = x.pollFirst(0L, TimeUnit.DAYS)) != null; )
                            sum[0] += e;
                        check.sum(sum[0]);}}},
            new Job(klazz + " timed pollLast()") {
                public void work() throws Throwable {
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(elements);
                        for (Integer e; (e = x.pollLast(0L, TimeUnit.DAYS)) != null; )
                            sum[0] += e;
                        check.sum(sum[0]);}}});
    }
}
Revision:	1.23
Committed:	Mon May 7 02:54:45 2018 UTC (6 years ago) by jsr166
Branch:	MAIN
Changes since 1.22:	+9 -0 lines
Log Message:	add Job for timed poll()
#	User	Rev	Content
1	jsr166	1.1	/*
2			* Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved.
3			* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4			*
5			* This code is free software; you can redistribute it and/or modify it
6			* under the terms of the GNU General Public License version 2 only, as
7			* published by the Free Software Foundation.
8			*
9			* This code is distributed in the hope that it will be useful, but WITHOUT
10			* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11			* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12			* version 2 for more details (a copy is included in the LICENSE file that
13			* accompanied this code).
14			*
15			* You should have received a copy of the GNU General Public License version
16			* 2 along with this work; if not, write to the Free Software Foundation,
17			* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18			*
19			* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20			* or visit www.oracle.com if you need additional information or have any
21			* questions.
22			*/
23
24			/*
25			* @test
26			* @summary micro-benchmark correctness mode
27			* @run main RemoveMicroBenchmark iterations=1 size=8 warmup=0
28			*/
29
30	jsr166	1.22	import static java.util.stream.Collectors.toCollection;
31	jsr166	1.20
32	jsr166	1.1	import java.lang.ref.WeakReference;
33			import java.util.ArrayDeque;
34			import java.util.ArrayList;
35			import java.util.Collection;
36	jsr166	1.5	import java.util.Collections;
37	jsr166	1.1	import java.util.Deque;
38	jsr166	1.22	import java.util.HashMap;
39	jsr166	1.1	import java.util.Iterator;
40			import java.util.LinkedList;
41			import java.util.List;
42			import java.util.ListIterator;
43	jsr166	1.2	import java.util.PriorityQueue;
44	jsr166	1.8	import java.util.Queue;
45	jsr166	1.1	import java.util.Vector;
46			import java.util.concurrent.ArrayBlockingQueue;
47	jsr166	1.7	import java.util.concurrent.BlockingDeque;
48	jsr166	1.3	import java.util.concurrent.BlockingQueue;
49	jsr166	1.1	import java.util.concurrent.ConcurrentLinkedDeque;
50			import java.util.concurrent.ConcurrentLinkedQueue;
51	jsr166	1.22	import java.util.concurrent.CopyOnWriteArrayList;
52	jsr166	1.2	import java.util.concurrent.CountDownLatch;
53	jsr166	1.1	import java.util.concurrent.LinkedBlockingDeque;
54			import java.util.concurrent.LinkedBlockingQueue;
55			import java.util.concurrent.LinkedTransferQueue;
56	jsr166	1.2	import java.util.concurrent.PriorityBlockingQueue;
57	jsr166	1.1	import java.util.concurrent.ThreadLocalRandom;
58			import java.util.concurrent.TimeUnit;
59			import java.util.regex.Pattern;
60	jsr166	1.22	import java.util.stream.Stream;
61	jsr166	1.1
62			/**
63			* Usage: [iterations=N] [size=N] [filter=REGEXP] [warmup=SECONDS]
64			*
65			* To run this in micro-benchmark mode, simply run as a normal java program.
66			* Be patient; this program runs for a very long time.
67			* For faster runs, restrict execution using command line args.
68			*
69			* @author Martin Buchholz
70			*/
71			public class RemoveMicroBenchmark {
72			abstract static class Job {
73			private final String name;
74			public Job(String name) { this.name = name; }
75			public String name() { return name; }
76			public abstract void work() throws Throwable;
77	jsr166	1.21	public void run() {
78			try { work(); }
79			catch (Throwable ex) {
80			// current job cannot always be deduced from stacktrace.
81			throw new RuntimeException("Job failed: " + name(), ex);
82			}
83			}
84	jsr166	1.1	}
85
86	jsr166	1.5	final int iterations;
87			final int size; // number of elements in collections
88			final double warmupSeconds;
89			final long warmupNanos;
90	jsr166	1.22	final Pattern nameFilter; // select subset of Jobs to run
91	jsr166	1.5	final boolean reverse; // reverse order of Jobs
92			final boolean shuffle; // randomize order of Jobs
93
94	jsr166	1.22	final ArrayList<Integer> elements; // contains size random Integers
95
96	jsr166	1.5	RemoveMicroBenchmark(String[] args) {
97			iterations = intArg(args, "iterations", 10_000);
98			size = intArg(args, "size", 1000);
99			warmupSeconds = doubleArg(args, "warmup", 7.0);
100	jsr166	1.22	nameFilter = patternArg(args, "filter");
101	jsr166	1.5	reverse = booleanArg(args, "reverse");
102			shuffle = booleanArg(args, "shuffle");
103
104			warmupNanos = (long) (warmupSeconds * (1000L * 1000L * 1000L));
105	jsr166	1.22
106			elements = ThreadLocalRandom.current().ints(size)
107			.mapToObj(x -> x)
108			.collect(toCollection(ArrayList::new));
109	jsr166	1.5	}
110	jsr166	1.1
111			// --------------- GC finalization infrastructure ---------------
112
113			/** No guarantees, but effective in practice. */
114			static void forceFullGc() {
115			CountDownLatch finalizeDone = new CountDownLatch(1);
116			WeakReference<?> ref = new WeakReference<Object>(new Object() {
117	jsr166	1.22	@SuppressWarnings("deprecation")
118	jsr166	1.1	protected void finalize() { finalizeDone.countDown(); }});
119			try {
120			for (int i = 0; i < 10; i++) {
121			System.gc();
122			if (finalizeDone.await(1L, TimeUnit.SECONDS) && ref.get() == null) {
123			System.runFinalization(); // try to pick up stragglers
124			return;
125			}
126			}
127			} catch (InterruptedException unexpected) {
128			throw new AssertionError("unexpected InterruptedException");
129			}
130			throw new AssertionError("failed to do a \"full\" gc");
131			}
132
133			/**
134			* Runs each job for long enough that all the runtime compilers
135			* have had plenty of time to warm up, i.e. get around to
136			* compiling everything worth compiling.
137			* Returns array of average times per job per run.
138			*/
139	jsr166	1.21	long[] time0(List<Job> jobs) {
140	jsr166	1.1	final int size = jobs.size();
141			long[] nanoss = new long[size];
142			for (int i = 0; i < size; i++) {
143			if (warmupNanos > 0) forceFullGc();
144	jsr166	1.4	Job job = jobs.get(i);
145			long totalTime;
146			int runs = 0;
147			long startTime = System.nanoTime();
148	jsr166	1.21	do { job.run(); runs++; }
149	jsr166	1.4	while ((totalTime = System.nanoTime() - startTime) < warmupNanos);
150			nanoss[i] = totalTime/runs;
151	jsr166	1.1	}
152			return nanoss;
153			}
154
155			void time(List<Job> jobs) throws Throwable {
156	jsr166	1.4	if (warmupNanos > 0) time0(jobs); // Warm up run
157	jsr166	1.1	final int size = jobs.size();
158			final long[] nanoss = time0(jobs); // Real timing run
159			final long[] milliss = new long[size];
160			final double[] ratios = new double[size];
161
162			final String nameHeader = "Method";
163			final String millisHeader = "Millis";
164			final String ratioHeader = "Ratio";
165
166			int nameWidth = nameHeader.length();
167			int millisWidth = millisHeader.length();
168			int ratioWidth = ratioHeader.length();
169
170			for (int i = 0; i < size; i++) {
171			nameWidth = Math.max(nameWidth, jobs.get(i).name().length());
172
173			milliss[i] = nanoss[i]/(1000L * 1000L);
174			millisWidth = Math.max(millisWidth,
175			String.format("%d", milliss[i]).length());
176
177			ratios[i] = (double) nanoss[i] / (double) nanoss[0];
178			ratioWidth = Math.max(ratioWidth,
179			String.format("%.3f", ratios[i]).length());
180			}
181
182			String format = String.format("%%-%ds %%%dd %%%d.3f%%n",
183			nameWidth, millisWidth, ratioWidth);
184			String headerFormat = String.format("%%-%ds %%%ds %%%ds%%n",
185			nameWidth, millisWidth, ratioWidth);
186			System.out.printf(headerFormat, "Method", "Millis", "Ratio");
187
188			// Print out absolute and relative times, calibrated against first job
189			for (int i = 0; i < size; i++)
190			System.out.printf(format, jobs.get(i).name(), milliss[i], ratios[i]);
191			}
192
193			private static String keywordValue(String[] args, String keyword) {
194			for (String arg : args)
195			if (arg.startsWith(keyword))
196			return arg.substring(keyword.length() + 1);
197			return null;
198			}
199
200			private static int intArg(String[] args, String keyword, int defaultValue) {
201			String val = keywordValue(args, keyword);
202			return (val == null) ? defaultValue : Integer.parseInt(val);
203			}
204
205			private static double doubleArg(String[] args, String keyword, double defaultValue) {
206			String val = keywordValue(args, keyword);
207			return (val == null) ? defaultValue : Double.parseDouble(val);
208			}
209
210			private static Pattern patternArg(String[] args, String keyword) {
211			String val = keywordValue(args, keyword);
212			return (val == null) ? null : Pattern.compile(val);
213			}
214
215	jsr166	1.5	private static boolean booleanArg(String[] args, String keyword) {
216			String val = keywordValue(args, keyword);
217			if (val == null \|\| val.equals("false")) return false;
218			if (val.equals("true")) return true;
219			throw new IllegalArgumentException(val);
220			}
221
222	jsr166	1.1	private static void deoptimize(int sum) {
223			if (sum == 42)
224			System.out.println("the answer");
225			}
226
227			private static <T> Iterable<T> backwards(final List<T> list) {
228			return new Iterable<T>() {
229			public Iterator<T> iterator() {
230			return new Iterator<T>() {
231			final ListIterator<T> it = list.listIterator(list.size());
232			public boolean hasNext() { return it.hasPrevious(); }
233			public T next() { return it.previous(); }
234			public void remove() { it.remove(); }};}};
235			}
236
237			// Checks for correctness and prevents loop optimizations
238	jsr166	1.18	static class Check {
239	jsr166	1.1	private int sum;
240			public void sum(int sum) {
241			if (this.sum == 0)
242			this.sum = sum;
243			if (this.sum != sum)
244			throw new AssertionError("Sum mismatch");
245			}
246			}
247			volatile Check check = new Check();
248
249			public static void main(String[] args) throws Throwable {
250	jsr166	1.5	new RemoveMicroBenchmark(args).run();
251	jsr166	1.1	}
252
253	jsr166	1.22	HashMap<Class<?>, String> goodClassName = new HashMap<>();
254	jsr166	1.1
255	jsr166	1.22	String goodClassName(Class<?> klazz) {
256			return goodClassName.computeIfAbsent(
257			klazz,
258			k -> {
259			String simple = k.getSimpleName();
260			return (simple.equals("SubList")) // too simple!
261			? k.getName().replaceFirst(".*\\.", "")
262			: simple;
263			});
264			}
265	jsr166	1.1
266	jsr166	1.22	static List<Integer> makeSubList(List<Integer> list) {
267	jsr166	1.1	final ThreadLocalRandom rnd = ThreadLocalRandom.current();
268	jsr166	1.22	int size = rnd.nextInt(4);
269			for (int i = size; i--> 0; )
270			list.add(rnd.nextInt());
271			int index = rnd.nextInt(size + 1);
272			return list.subList(index, index);
273			}
274
275			private static <T> List<T> asSubList(List<T> list) {
276			return list.subList(0, list.size());
277			}
278
279			@SafeVarargs @SuppressWarnings("varargs")
280			private <T> Stream<T> concatStreams(Stream<T> ... streams) {
281			return Stream.of(streams).flatMap(s -> s);
282			}
283	jsr166	1.1
284	jsr166	1.22	Class<?> topLevelClass(Object x) {
285			for (Class<?> k = x.getClass();; ) {
286			Class<?> enclosing = k.getEnclosingClass();
287			if (enclosing == null)
288			return k;
289			k = enclosing;
290			}
291			}
292	jsr166	1.1
293	jsr166	1.22	void run() throws Throwable {
294			ArrayList<Job> jobs = Stream.<Collection<Integer>>of(
295			new ArrayList<>(),
296			makeSubList(new ArrayList<>()),
297			new LinkedList<>(),
298			makeSubList(new LinkedList<>()),
299			new Vector<>(),
300			makeSubList(new Vector<>()),
301			new CopyOnWriteArrayList<>(),
302			makeSubList(new CopyOnWriteArrayList<>()),
303			new ArrayDeque<>(),
304			new PriorityQueue<>(),
305			new ArrayBlockingQueue<>(elements.size()),
306			new ConcurrentLinkedQueue<>(),
307			new ConcurrentLinkedDeque<>(),
308			new LinkedBlockingQueue<>(),
309			new LinkedBlockingDeque<>(),
310			new LinkedTransferQueue<>(),
311			new PriorityBlockingQueue<>())
312			.flatMap(x -> jobs(x))
313			.filter(job ->
314			nameFilter == null \|\| nameFilter.matcher(job.name()).find())
315			.collect(toCollection(ArrayList::new));
316	jsr166	1.1
317	jsr166	1.5	if (reverse) Collections.reverse(jobs);
318			if (shuffle) Collections.shuffle(jobs);
319
320	jsr166	1.22	time(jobs);
321			}
322
323			Stream<Job> jobs(Collection<Integer> x) {
324			return concatStreams(
325			collectionJobs(x),
326
327			(CopyOnWriteArrayList.class.isAssignableFrom(topLevelClass(x)))
328			? Stream.empty()
329			: iteratorRemoveJobs(x),
330
331			(x instanceof Queue)
332			? queueJobs((Queue<Integer>)x)
333			: Stream.empty(),
334
335			(x instanceof Deque)
336			? dequeJobs((Deque<Integer>)x)
337			: Stream.empty(),
338
339			(x instanceof BlockingQueue)
340			? blockingQueueJobs((BlockingQueue<Integer>)x)
341			: Stream.empty(),
342
343			(x instanceof BlockingDeque)
344			? blockingDequeJobs((BlockingDeque<Integer>)x)
345			: Stream.empty());
346	jsr166	1.1	}
347
348			Collection<Integer> universeRecorder(int[] sum) {
349			return new ArrayList<>() {
350			public boolean contains(Object x) {
351			sum[0] += (Integer) x;
352			return true;
353			}};
354			}
355
356			Collection<Integer> emptyRecorder(int[] sum) {
357			return new ArrayList<>() {
358			public boolean contains(Object x) {
359			sum[0] += (Integer) x;
360			return false;
361			}};
362			}
363
364	jsr166	1.22	Stream<Job> collectionJobs(Collection<Integer> x) {
365			final String klazz = goodClassName(x.getClass());
366			return Stream.of(
367			new Job(klazz + " removeIf") {
368	jsr166	1.1	public void work() throws Throwable {
369			int[] sum = new int[1];
370			for (int i = 0; i < iterations; i++) {
371			sum[0] = 0;
372	jsr166	1.22	x.addAll(elements);
373	jsr166	1.1	x.removeIf(n -> { sum[0] += n; return true; });
374			check.sum(sum[0]);}}},
375	jsr166	1.22	new Job(klazz + " removeIf rnd-two-pass") {
376	jsr166	1.9	public void work() throws Throwable {
377			ThreadLocalRandom rnd = ThreadLocalRandom.current();
378			int[] sum = new int[1];
379			for (int i = 0; i < iterations; i++) {
380			sum[0] = 0;
381	jsr166	1.22	x.addAll(elements);
382	jsr166	1.9	x.removeIf(n -> {
383			boolean b = rnd.nextBoolean();
384			if (b) sum[0] += n;
385			return b; });
386			x.removeIf(n -> { sum[0] += n; return true; });
387			check.sum(sum[0]);}}},
388	jsr166	1.22	new Job(klazz + " removeAll") {
389	jsr166	1.1	public void work() throws Throwable {
390			int[] sum = new int[1];
391			Collection<Integer> universe = universeRecorder(sum);
392			for (int i = 0; i < iterations; i++) {
393			sum[0] = 0;
394	jsr166	1.22	x.addAll(elements);
395	jsr166	1.1	x.removeAll(universe);
396			check.sum(sum[0]);}}},
397	jsr166	1.22	new Job(klazz + " retainAll") {
398	jsr166	1.1	public void work() throws Throwable {
399			int[] sum = new int[1];
400			Collection<Integer> empty = emptyRecorder(sum);
401			for (int i = 0; i < iterations; i++) {
402			sum[0] = 0;
403	jsr166	1.22	x.addAll(elements);
404	jsr166	1.1	x.retainAll(empty);
405			check.sum(sum[0]);}}},
406	jsr166	1.22	new Job(klazz + " clear") {
407			public void work() throws Throwable {
408			int[] sum = new int[1];
409			for (int i = 0; i < iterations; i++) {
410			sum[0] = 0;
411			x.addAll(elements);
412			x.forEach(e -> sum[0] += e);
413			x.clear();
414			check.sum(sum[0]);}}});
415			}
416
417			Stream<Job> iteratorRemoveJobs(Collection<Integer> x) {
418			final String klazz = goodClassName(x.getClass());
419			return Stream.of(
420			new Job(klazz + " Iterator.remove") {
421	jsr166	1.1	public void work() throws Throwable {
422			int[] sum = new int[1];
423			for (int i = 0; i < iterations; i++) {
424			sum[0] = 0;
425	jsr166	1.22	x.addAll(elements);
426	jsr166	1.1	Iterator<Integer> it = x.iterator();
427			while (it.hasNext()) {
428			sum[0] += it.next();
429			it.remove();
430			}
431			check.sum(sum[0]);}}},
432	jsr166	1.22	new Job(klazz + " Iterator.remove-rnd-two-pass") {
433	jsr166	1.10	public void work() throws Throwable {
434			ThreadLocalRandom rnd = ThreadLocalRandom.current();
435			int[] sum = new int[1];
436			for (int i = 0; i < iterations; i++) {
437			sum[0] = 0;
438	jsr166	1.22	x.addAll(elements);
439	jsr166	1.12	for (Iterator<Integer> it = x.iterator();
440			it.hasNext(); ) {
441			Integer e = it.next();
442	jsr166	1.10	if (rnd.nextBoolean()) {
443	jsr166	1.12	sum[0] += e;
444	jsr166	1.10	it.remove();
445			}
446			}
447	jsr166	1.12	for (Iterator<Integer> it = x.iterator();
448			it.hasNext(); ) {
449	jsr166	1.10	sum[0] += it.next();
450			it.remove();
451			}
452	jsr166	1.1	check.sum(sum[0]);}}});
453			}
454
455	jsr166	1.22	Stream<Job> queueJobs(Queue<Integer> x) {
456			final String klazz = goodClassName(x.getClass());
457			return Stream.of(
458			new Job(klazz + " poll()") {
459	jsr166	1.8	public void work() throws Throwable {
460			int[] sum = new int[1];
461			for (int i = 0; i < iterations; i++) {
462			sum[0] = 0;
463	jsr166	1.22	x.addAll(elements);
464	jsr166	1.8	for (Integer e; (e = x.poll()) != null; )
465			sum[0] += e;
466			check.sum(sum[0]);}}});
467			}
468
469	jsr166	1.22	Stream<Job> dequeJobs(Deque<Integer> x) {
470			final String klazz = goodClassName(x.getClass());
471			return Stream.of(
472			new Job(klazz + " descendingIterator().remove") {
473	jsr166	1.1	public void work() throws Throwable {
474			int[] sum = new int[1];
475			for (int i = 0; i < iterations; i++) {
476			sum[0] = 0;
477	jsr166	1.22	x.addAll(elements);
478	jsr166	1.1	Iterator<Integer> it = x.descendingIterator();
479			while (it.hasNext()) {
480			sum[0] += it.next();
481			it.remove();
482			}
483	jsr166	1.6	check.sum(sum[0]);}}},
484	jsr166	1.22	new Job(klazz + " pollFirst()") {
485	jsr166	1.6	public void work() throws Throwable {
486			int[] sum = new int[1];
487			for (int i = 0; i < iterations; i++) {
488			sum[0] = 0;
489	jsr166	1.22	x.addAll(elements);
490	jsr166	1.6	for (Integer e; (e = x.pollFirst()) != null; )
491			sum[0] += e;
492			check.sum(sum[0]);}}},
493	jsr166	1.22	new Job(klazz + " pollLast()") {
494	jsr166	1.6	public void work() throws Throwable {
495			int[] sum = new int[1];
496			for (int i = 0; i < iterations; i++) {
497			sum[0] = 0;
498	jsr166	1.22	x.addAll(elements);
499	jsr166	1.6	for (Integer e; (e = x.pollLast()) != null; )
500			sum[0] += e;
501	jsr166	1.1	check.sum(sum[0]);}}});
502			}
503	jsr166	1.3
504	jsr166	1.22	Stream<Job> blockingQueueJobs(BlockingQueue<Integer> x) {
505			final String klazz = goodClassName(x.getClass());
506			return Stream.of(
507	jsr166	1.23	new Job(klazz + " timed poll()") {
508			public void work() throws Throwable {
509			int[] sum = new int[1];
510			for (int i = 0; i < iterations; i++) {
511			sum[0] = 0;
512			x.addAll(elements);
513			for (Integer e; (e = x.poll(0L, TimeUnit.DAYS)) != null; )
514			sum[0] += e;
515			check.sum(sum[0]);}}},
516	jsr166	1.22	new Job(klazz + " drainTo(sink)") {
517	jsr166	1.3	public void work() throws Throwable {
518			ArrayList<Integer> sink = new ArrayList<>();
519			int[] sum = new int[1];
520			for (int i = 0; i < iterations; i++) {
521			sum[0] = 0;
522			sink.clear();
523	jsr166	1.22	x.addAll(elements);
524	jsr166	1.3	x.drainTo(sink);
525			sink.forEach(e -> sum[0] += e);
526			check.sum(sum[0]);}}},
527	jsr166	1.22	new Job(klazz + " drainTo(sink, n)") {
528	jsr166	1.3	public void work() throws Throwable {
529			ArrayList<Integer> sink = new ArrayList<>();
530			int[] sum = new int[1];
531			for (int i = 0; i < iterations; i++) {
532			sum[0] = 0;
533			sink.clear();
534	jsr166	1.22	x.addAll(elements);
535			x.drainTo(sink, elements.size());
536	jsr166	1.3	sink.forEach(e -> sum[0] += e);
537			check.sum(sum[0]);}}});
538			}
539	jsr166	1.7
540	jsr166	1.22	Stream<Job> blockingDequeJobs(BlockingDeque<Integer> x) {
541			final String klazz = goodClassName(x.getClass());
542			return Stream.of(
543			new Job(klazz + " timed pollFirst()") {
544	jsr166	1.7	public void work() throws Throwable {
545			int[] sum = new int[1];
546			for (int i = 0; i < iterations; i++) {
547			sum[0] = 0;
548	jsr166	1.22	x.addAll(elements);
549	jsr166	1.7	for (Integer e; (e = x.pollFirst(0L, TimeUnit.DAYS)) != null; )
550			sum[0] += e;
551			check.sum(sum[0]);}}},
552	jsr166	1.22	new Job(klazz + " timed pollLast()") {
553	jsr166	1.7	public void work() throws Throwable {
554			int[] sum = new int[1];
555			for (int i = 0; i < iterations; i++) {
556			sum[0] = 0;
557	jsr166	1.22	x.addAll(elements);
558	jsr166	1.7	for (Integer e; (e = x.pollLast(0L, TimeUnit.DAYS)) != null; )
559			sum[0] += e;
560			check.sum(sum[0]);}}});
561			}
562	jsr166	1.1	}