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 java.lang.ref.WeakReference;
import java.util.ArrayDeque;
import java.util.Arrays;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Deque;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.ListIterator;
import java.util.Map;
import java.util.PriorityQueue;
import java.util.Spliterator;
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.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.function.Supplier;

/**
 * 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;
    }

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

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

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

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

    /** No guarantees, but effective in practice. */
    static void forceFullGc() {
        CountDownLatch finalizeDone = new CountDownLatch(1);
        WeakReference<?> ref = new WeakReference<Object>(new Object() {
            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) throws Throwable {
        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.work(); 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 List<Job> filter(Pattern filter, List<Job> jobs) {
        if (filter == null) return jobs;
        ArrayList<Job> newJobs = new ArrayList<>();
        for (Job job : jobs)
            if (filter.matcher(job.name()).find())
                newJobs.add(job);
        return newJobs;
    }

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

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

    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
    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();
    }

    void run() throws Throwable {
//         System.out.printf(
//             "iterations=%d size=%d, warmup=%1g, filter=\"%s\"%n",
//             iterations, size, warmupSeconds, filter);

        final ArrayList<Integer> al = new ArrayList<Integer>(size);

        // Populate collections with random data
        final ThreadLocalRandom rnd = ThreadLocalRandom.current();
        for (int i = 0; i < size; i++)
            al.add(rnd.nextInt(size));

        ArrayList<Job> jobs = new ArrayList<>();

        List.<Collection<Integer>>of(
            new ArrayList<>(),
            new LinkedList<>(),
            new Vector<>(),
            new ArrayDeque<>(),
            new PriorityQueue<>(),
            new ArrayBlockingQueue<>(al.size()),
            new ConcurrentLinkedQueue<>(),
            new ConcurrentLinkedDeque<>(),
            new LinkedBlockingQueue<>(),
            new LinkedBlockingDeque<>(),
            new LinkedTransferQueue<>(),
            new PriorityBlockingQueue<>())
            .stream().forEach(
                x -> {
                    String klazz = x.getClass().getSimpleName();
                    jobs.addAll(collectionJobs(klazz, () -> x, al));
                    if (x instanceof Deque) {
                        Deque<Integer> deque = (Deque<Integer>) x;
                        jobs.addAll(dequeJobs(klazz, () -> deque, al));
                    }
                    if (x instanceof BlockingQueue) {
                        BlockingQueue<Integer> q = (BlockingQueue<Integer>) x;
                        jobs.addAll(blockingQueueJobs(klazz, () -> q, al));
                    }
                    if (x instanceof BlockingDeque) {
                        BlockingDeque<Integer> q = (BlockingDeque<Integer>) x;
                        jobs.addAll(blockingDequeJobs(klazz, () -> q, al));
                    }
                    if (x instanceof List) {
                        List<Integer> list = (List<Integer>) x;
                        jobs.addAll(
                            collectionJobs(
                                klazz + " subList",
                                () -> list.subList(0, x.size()),
                                al));
                    }
                });

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

        time(filter(filter, jobs));
    }

    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;
            }};
    }

    List<Job> collectionJobs(
        String description,
        Supplier<Collection<Integer>> supplier,
        ArrayList<Integer> al) {
        return List.of(
            new Job(description + " .removeIf") {
                public void work() throws Throwable {
                    Collection<Integer> x = supplier.get();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(al);
                        x.removeIf(n -> { sum[0] += n; return true; });
                        check.sum(sum[0]);}}},
            new Job(description + " .removeAll") {
                public void work() throws Throwable {
                    Collection<Integer> x = supplier.get();
                    int[] sum = new int[1];
                    Collection<Integer> universe = universeRecorder(sum);
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(al);
                        x.removeAll(universe);
                        check.sum(sum[0]);}}},
            new Job(description + " .retainAll") {
                public void work() throws Throwable {
                    Collection<Integer> x = supplier.get();
                    int[] sum = new int[1];
                    Collection<Integer> empty = emptyRecorder(sum);
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(al);
                        x.retainAll(empty);
                        check.sum(sum[0]);}}},
            new Job(description + " Iterator.remove") {
                public void work() throws Throwable {
                    Collection<Integer> x = supplier.get();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(al);
                        Iterator<Integer> it = x.iterator();
                        while (it.hasNext()) {
                            sum[0] += it.next();
                            it.remove();
                        }
                        check.sum(sum[0]);}}},
            new Job(description + " clear") {
                public void work() throws Throwable {
                    Collection<Integer> x = supplier.get();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(al);
                        x.forEach(e -> sum[0] += e);
                        x.clear();
                        check.sum(sum[0]);}}});
    }

    List<Job> dequeJobs(
        String description,
        Supplier<Deque<Integer>> supplier,
        ArrayList<Integer> al) {
        return List.of(
            new Job(description + " descendingIterator().remove") {
                public void work() throws Throwable {
                    Deque<Integer> x = supplier.get();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(al);
                        Iterator<Integer> it = x.descendingIterator();
                        while (it.hasNext()) {
                            sum[0] += it.next();
                            it.remove();
                        }
                        check.sum(sum[0]);}}},
            new Job(description + " pollFirst()") {
                public void work() throws Throwable {
                    Deque<Integer> x = supplier.get();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(al);
                        for (Integer e; (e = x.pollFirst()) != null; )
                            sum[0] += e;
                        check.sum(sum[0]);}}},
            new Job(description + " pollLast()") {
                public void work() throws Throwable {
                    Deque<Integer> x = supplier.get();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(al);
                        for (Integer e; (e = x.pollLast()) != null; )
                            sum[0] += e;
                        check.sum(sum[0]);}}});
    }

    List<Job> blockingQueueJobs(
        String description,
        Supplier<BlockingQueue<Integer>> supplier,
        ArrayList<Integer> al) {
        return List.of(
            new Job(description + " drainTo(sink)") {
                public void work() throws Throwable {
                    BlockingQueue<Integer> x = supplier.get();
                    ArrayList<Integer> sink = new ArrayList<>();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        sink.clear();
                        x.addAll(al);
                        x.drainTo(sink);
                        sink.forEach(e -> sum[0] += e);
                        check.sum(sum[0]);}}},
            new Job(description + " drainTo(sink, n)") {
                public void work() throws Throwable {
                    BlockingQueue<Integer> x = supplier.get();
                    ArrayList<Integer> sink = new ArrayList<>();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        sink.clear();
                        x.addAll(al);
                        x.drainTo(sink, al.size());
                        sink.forEach(e -> sum[0] += e);
                        check.sum(sum[0]);}}});
    }

    List<Job> blockingDequeJobs(
        String description,
        Supplier<BlockingDeque<Integer>> supplier,
        ArrayList<Integer> al) {
        return List.of(
            new Job(description + " timed pollFirst()") {
                public void work() throws Throwable {
                    BlockingDeque<Integer> x = supplier.get();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(al);
                        for (Integer e; (e = x.pollFirst(0L, TimeUnit.DAYS)) != null; )
                            sum[0] += e;
                        check.sum(sum[0]);}}},
            new Job(description + " timed pollLast()") {
                public void work() throws Throwable {
                    BlockingDeque<Integer> x = supplier.get();
                    int[] sum = new int[1];
                    for (int i = 0; i < iterations; i++) {
                        sum[0] = 0;
                        x.addAll(al);
                        for (Integer e; (e = x.pollLast(0L, TimeUnit.DAYS)) != null; )
                            sum[0] += e;
                        check.sum(sum[0]);}}});
    }
}
Revision:	1.7
Committed:	Sun Nov 27 22:13:19 2016 UTC (7 years, 6 months ago) by jsr166
Branch:	MAIN
Changes since 1.6:	+32 -0 lines
Log Message:	add timed pollFirst, pollLast
#	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			import java.lang.ref.WeakReference;
31			import java.util.ArrayDeque;
32			import java.util.Arrays;
33			import java.util.ArrayList;
34			import java.util.Collection;
35	jsr166	1.5	import java.util.Collections;
36	jsr166	1.1	import java.util.Deque;
37			import java.util.Enumeration;
38			import java.util.Iterator;
39			import java.util.LinkedList;
40			import java.util.List;
41			import java.util.ListIterator;
42			import java.util.Map;
43	jsr166	1.2	import java.util.PriorityQueue;
44	jsr166	1.1	import java.util.Spliterator;
45			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	1.2	import java.util.concurrent.CountDownLatch;
52	jsr166	1.1	import java.util.concurrent.LinkedBlockingDeque;
53			import java.util.concurrent.LinkedBlockingQueue;
54			import java.util.concurrent.LinkedTransferQueue;
55	jsr166	1.2	import java.util.concurrent.PriorityBlockingQueue;
56	jsr166	1.1	import java.util.concurrent.ThreadLocalRandom;
57			import java.util.concurrent.TimeUnit;
58			import java.util.regex.Pattern;
59			import java.util.function.Supplier;
60
61			/**
62			* Usage: [iterations=N] [size=N] [filter=REGEXP] [warmup=SECONDS]
63			*
64			* To run this in micro-benchmark mode, simply run as a normal java program.
65			* Be patient; this program runs for a very long time.
66			* For faster runs, restrict execution using command line args.
67			*
68			* @author Martin Buchholz
69			*/
70			public class RemoveMicroBenchmark {
71			abstract static class Job {
72			private final String name;
73			public Job(String name) { this.name = name; }
74			public String name() { return name; }
75			public abstract void work() throws Throwable;
76			}
77
78	jsr166	1.5	final int iterations;
79			final int size; // number of elements in collections
80			final double warmupSeconds;
81			final long warmupNanos;
82			final Pattern filter; // select subset of Jobs to run
83			final boolean reverse; // reverse order of Jobs
84			final boolean shuffle; // randomize order of Jobs
85
86			RemoveMicroBenchmark(String[] args) {
87			iterations = intArg(args, "iterations", 10_000);
88			size = intArg(args, "size", 1000);
89			warmupSeconds = doubleArg(args, "warmup", 7.0);
90			filter = patternArg(args, "filter");
91			reverse = booleanArg(args, "reverse");
92			shuffle = booleanArg(args, "shuffle");
93
94			warmupNanos = (long) (warmupSeconds * (1000L * 1000L * 1000L));
95			}
96	jsr166	1.1
97			// --------------- GC finalization infrastructure ---------------
98
99			/** No guarantees, but effective in practice. */
100			static void forceFullGc() {
101			CountDownLatch finalizeDone = new CountDownLatch(1);
102			WeakReference<?> ref = new WeakReference<Object>(new Object() {
103			protected void finalize() { finalizeDone.countDown(); }});
104			try {
105			for (int i = 0; i < 10; i++) {
106			System.gc();
107			if (finalizeDone.await(1L, TimeUnit.SECONDS) && ref.get() == null) {
108			System.runFinalization(); // try to pick up stragglers
109			return;
110			}
111			}
112			} catch (InterruptedException unexpected) {
113			throw new AssertionError("unexpected InterruptedException");
114			}
115			throw new AssertionError("failed to do a \"full\" gc");
116			}
117
118			/**
119			* Runs each job for long enough that all the runtime compilers
120			* have had plenty of time to warm up, i.e. get around to
121			* compiling everything worth compiling.
122			* Returns array of average times per job per run.
123			*/
124			long[] time0(List<Job> jobs) throws Throwable {
125			final int size = jobs.size();
126			long[] nanoss = new long[size];
127			for (int i = 0; i < size; i++) {
128			if (warmupNanos > 0) forceFullGc();
129	jsr166	1.4	Job job = jobs.get(i);
130			long totalTime;
131			int runs = 0;
132			long startTime = System.nanoTime();
133			do { job.work(); runs++; }
134			while ((totalTime = System.nanoTime() - startTime) < warmupNanos);
135			nanoss[i] = totalTime/runs;
136	jsr166	1.1	}
137			return nanoss;
138			}
139
140			void time(List<Job> jobs) throws Throwable {
141	jsr166	1.4	if (warmupNanos > 0) time0(jobs); // Warm up run
142	jsr166	1.1	final int size = jobs.size();
143			final long[] nanoss = time0(jobs); // Real timing run
144			final long[] milliss = new long[size];
145			final double[] ratios = new double[size];
146
147			final String nameHeader = "Method";
148			final String millisHeader = "Millis";
149			final String ratioHeader = "Ratio";
150
151			int nameWidth = nameHeader.length();
152			int millisWidth = millisHeader.length();
153			int ratioWidth = ratioHeader.length();
154
155			for (int i = 0; i < size; i++) {
156			nameWidth = Math.max(nameWidth, jobs.get(i).name().length());
157
158			milliss[i] = nanoss[i]/(1000L * 1000L);
159			millisWidth = Math.max(millisWidth,
160			String.format("%d", milliss[i]).length());
161
162			ratios[i] = (double) nanoss[i] / (double) nanoss[0];
163			ratioWidth = Math.max(ratioWidth,
164			String.format("%.3f", ratios[i]).length());
165			}
166
167			String format = String.format("%%-%ds %%%dd %%%d.3f%%n",
168			nameWidth, millisWidth, ratioWidth);
169			String headerFormat = String.format("%%-%ds %%%ds %%%ds%%n",
170			nameWidth, millisWidth, ratioWidth);
171			System.out.printf(headerFormat, "Method", "Millis", "Ratio");
172
173			// Print out absolute and relative times, calibrated against first job
174			for (int i = 0; i < size; i++)
175			System.out.printf(format, jobs.get(i).name(), milliss[i], ratios[i]);
176			}
177
178			private static String keywordValue(String[] args, String keyword) {
179			for (String arg : args)
180			if (arg.startsWith(keyword))
181			return arg.substring(keyword.length() + 1);
182			return null;
183			}
184
185			private static int intArg(String[] args, String keyword, int defaultValue) {
186			String val = keywordValue(args, keyword);
187			return (val == null) ? defaultValue : Integer.parseInt(val);
188			}
189
190			private static double doubleArg(String[] args, String keyword, double defaultValue) {
191			String val = keywordValue(args, keyword);
192			return (val == null) ? defaultValue : Double.parseDouble(val);
193			}
194
195			private static Pattern patternArg(String[] args, String keyword) {
196			String val = keywordValue(args, keyword);
197			return (val == null) ? null : Pattern.compile(val);
198			}
199
200	jsr166	1.5	private static boolean booleanArg(String[] args, String keyword) {
201			String val = keywordValue(args, keyword);
202			if (val == null \|\| val.equals("false")) return false;
203			if (val.equals("true")) return true;
204			throw new IllegalArgumentException(val);
205			}
206
207	jsr166	1.1	private static List<Job> filter(Pattern filter, List<Job> jobs) {
208			if (filter == null) return jobs;
209			ArrayList<Job> newJobs = new ArrayList<>();
210			for (Job job : jobs)
211			if (filter.matcher(job.name()).find())
212			newJobs.add(job);
213			return newJobs;
214			}
215
216			private static void deoptimize(int sum) {
217			if (sum == 42)
218			System.out.println("the answer");
219			}
220
221			private static <T> List<T> asSubList(List<T> list) {
222			return list.subList(0, list.size());
223			}
224
225			private static <T> Iterable<T> backwards(final List<T> list) {
226			return new Iterable<T>() {
227			public Iterator<T> iterator() {
228			return new Iterator<T>() {
229			final ListIterator<T> it = list.listIterator(list.size());
230			public boolean hasNext() { return it.hasPrevious(); }
231			public T next() { return it.previous(); }
232			public void remove() { it.remove(); }};}};
233			}
234
235			// Checks for correctness and prevents loop optimizations
236			class Check {
237			private int sum;
238			public void sum(int sum) {
239			if (this.sum == 0)
240			this.sum = sum;
241			if (this.sum != sum)
242			throw new AssertionError("Sum mismatch");
243			}
244			}
245			volatile Check check = new Check();
246
247			public static void main(String[] args) throws Throwable {
248	jsr166	1.5	new RemoveMicroBenchmark(args).run();
249	jsr166	1.1	}
250
251	jsr166	1.5	void run() throws Throwable {
252	jsr166	1.1	// System.out.printf(
253			// "iterations=%d size=%d, warmup=%1g, filter=\"%s\"%n",
254			// iterations, size, warmupSeconds, filter);
255
256			final ArrayList<Integer> al = new ArrayList<Integer>(size);
257
258			// Populate collections with random data
259			final ThreadLocalRandom rnd = ThreadLocalRandom.current();
260			for (int i = 0; i < size; i++)
261			al.add(rnd.nextInt(size));
262
263			ArrayList<Job> jobs = new ArrayList<>();
264
265			List.<Collection<Integer>>of(
266			new ArrayList<>(),
267			new LinkedList<>(),
268			new Vector<>(),
269			new ArrayDeque<>(),
270	jsr166	1.2	new PriorityQueue<>(),
271	jsr166	1.1	new ArrayBlockingQueue<>(al.size()),
272			new ConcurrentLinkedQueue<>(),
273			new ConcurrentLinkedDeque<>(),
274			new LinkedBlockingQueue<>(),
275			new LinkedBlockingDeque<>(),
276	jsr166	1.2	new LinkedTransferQueue<>(),
277			new PriorityBlockingQueue<>())
278	jsr166	1.1	.stream().forEach(
279			x -> {
280			String klazz = x.getClass().getSimpleName();
281			jobs.addAll(collectionJobs(klazz, () -> x, al));
282			if (x instanceof Deque) {
283			Deque<Integer> deque = (Deque<Integer>) x;
284			jobs.addAll(dequeJobs(klazz, () -> deque, al));
285			}
286	jsr166	1.3	if (x instanceof BlockingQueue) {
287			BlockingQueue<Integer> q = (BlockingQueue<Integer>) x;
288			jobs.addAll(blockingQueueJobs(klazz, () -> q, al));
289			}
290	jsr166	1.7	if (x instanceof BlockingDeque) {
291			BlockingDeque<Integer> q = (BlockingDeque<Integer>) x;
292			jobs.addAll(blockingDequeJobs(klazz, () -> q, al));
293			}
294	jsr166	1.1	if (x instanceof List) {
295			List<Integer> list = (List<Integer>) x;
296			jobs.addAll(
297			collectionJobs(
298			klazz + " subList",
299			() -> list.subList(0, x.size()),
300			al));
301			}
302			});
303
304	jsr166	1.5	if (reverse) Collections.reverse(jobs);
305			if (shuffle) Collections.shuffle(jobs);
306
307	jsr166	1.1	time(filter(filter, jobs));
308			}
309
310			Collection<Integer> universeRecorder(int[] sum) {
311			return new ArrayList<>() {
312			public boolean contains(Object x) {
313			sum[0] += (Integer) x;
314			return true;
315			}};
316			}
317
318			Collection<Integer> emptyRecorder(int[] sum) {
319			return new ArrayList<>() {
320			public boolean contains(Object x) {
321			sum[0] += (Integer) x;
322			return false;
323			}};
324			}
325
326			List<Job> collectionJobs(
327			String description,
328			Supplier<Collection<Integer>> supplier,
329			ArrayList<Integer> al) {
330			return List.of(
331			new Job(description + " .removeIf") {
332			public void work() throws Throwable {
333			Collection<Integer> x = supplier.get();
334			int[] sum = new int[1];
335			for (int i = 0; i < iterations; i++) {
336			sum[0] = 0;
337			x.addAll(al);
338			x.removeIf(n -> { sum[0] += n; return true; });
339			check.sum(sum[0]);}}},
340			new Job(description + " .removeAll") {
341			public void work() throws Throwable {
342			Collection<Integer> x = supplier.get();
343			int[] sum = new int[1];
344			Collection<Integer> universe = universeRecorder(sum);
345			for (int i = 0; i < iterations; i++) {
346			sum[0] = 0;
347			x.addAll(al);
348			x.removeAll(universe);
349			check.sum(sum[0]);}}},
350			new Job(description + " .retainAll") {
351			public void work() throws Throwable {
352			Collection<Integer> x = supplier.get();
353			int[] sum = new int[1];
354			Collection<Integer> empty = emptyRecorder(sum);
355			for (int i = 0; i < iterations; i++) {
356			sum[0] = 0;
357			x.addAll(al);
358			x.retainAll(empty);
359			check.sum(sum[0]);}}},
360			new Job(description + " Iterator.remove") {
361			public void work() throws Throwable {
362			Collection<Integer> x = supplier.get();
363			int[] sum = new int[1];
364			for (int i = 0; i < iterations; i++) {
365			sum[0] = 0;
366			x.addAll(al);
367			Iterator<Integer> it = x.iterator();
368			while (it.hasNext()) {
369			sum[0] += it.next();
370			it.remove();
371			}
372			check.sum(sum[0]);}}},
373			new Job(description + " clear") {
374			public void work() throws Throwable {
375			Collection<Integer> x = supplier.get();
376			int[] sum = new int[1];
377			for (int i = 0; i < iterations; i++) {
378			sum[0] = 0;
379			x.addAll(al);
380			x.forEach(e -> sum[0] += e);
381			x.clear();
382			check.sum(sum[0]);}}});
383			}
384
385			List<Job> dequeJobs(
386			String description,
387			Supplier<Deque<Integer>> supplier,
388			ArrayList<Integer> al) {
389			return List.of(
390			new Job(description + " descendingIterator().remove") {
391			public void work() throws Throwable {
392			Deque<Integer> x = supplier.get();
393			int[] sum = new int[1];
394			for (int i = 0; i < iterations; i++) {
395			sum[0] = 0;
396			x.addAll(al);
397			Iterator<Integer> it = x.descendingIterator();
398			while (it.hasNext()) {
399			sum[0] += it.next();
400			it.remove();
401			}
402	jsr166	1.6	check.sum(sum[0]);}}},
403			new Job(description + " pollFirst()") {
404			public void work() throws Throwable {
405			Deque<Integer> x = supplier.get();
406			int[] sum = new int[1];
407			for (int i = 0; i < iterations; i++) {
408			sum[0] = 0;
409			x.addAll(al);
410			for (Integer e; (e = x.pollFirst()) != null; )
411			sum[0] += e;
412			check.sum(sum[0]);}}},
413			new Job(description + " pollLast()") {
414			public void work() throws Throwable {
415			Deque<Integer> x = supplier.get();
416			int[] sum = new int[1];
417			for (int i = 0; i < iterations; i++) {
418			sum[0] = 0;
419			x.addAll(al);
420			for (Integer e; (e = x.pollLast()) != null; )
421			sum[0] += e;
422	jsr166	1.1	check.sum(sum[0]);}}});
423			}
424	jsr166	1.3
425			List<Job> blockingQueueJobs(
426			String description,
427			Supplier<BlockingQueue<Integer>> supplier,
428			ArrayList<Integer> al) {
429			return List.of(
430			new Job(description + " drainTo(sink)") {
431			public void work() throws Throwable {
432			BlockingQueue<Integer> x = supplier.get();
433			ArrayList<Integer> sink = new ArrayList<>();
434			int[] sum = new int[1];
435			for (int i = 0; i < iterations; i++) {
436			sum[0] = 0;
437			sink.clear();
438			x.addAll(al);
439			x.drainTo(sink);
440			sink.forEach(e -> sum[0] += e);
441			check.sum(sum[0]);}}},
442			new Job(description + " drainTo(sink, n)") {
443			public void work() throws Throwable {
444			BlockingQueue<Integer> x = supplier.get();
445			ArrayList<Integer> sink = new ArrayList<>();
446			int[] sum = new int[1];
447			for (int i = 0; i < iterations; i++) {
448			sum[0] = 0;
449			sink.clear();
450			x.addAll(al);
451			x.drainTo(sink, al.size());
452			sink.forEach(e -> sum[0] += e);
453			check.sum(sum[0]);}}});
454			}
455	jsr166	1.7
456			List<Job> blockingDequeJobs(
457			String description,
458			Supplier<BlockingDeque<Integer>> supplier,
459			ArrayList<Integer> al) {
460			return List.of(
461			new Job(description + " timed pollFirst()") {
462			public void work() throws Throwable {
463			BlockingDeque<Integer> x = supplier.get();
464			int[] sum = new int[1];
465			for (int i = 0; i < iterations; i++) {
466			sum[0] = 0;
467			x.addAll(al);
468			for (Integer e; (e = x.pollFirst(0L, TimeUnit.DAYS)) != null; )
469			sum[0] += e;
470			check.sum(sum[0]);}}},
471			new Job(description + " timed pollLast()") {
472			public void work() throws Throwable {
473			BlockingDeque<Integer> x = supplier.get();
474			int[] sum = new int[1];
475			for (int i = 0; i < iterations; i++) {
476			sum[0] = 0;
477			x.addAll(al);
478			for (Integer e; (e = x.pollLast(0L, TimeUnit.DAYS)) != null; )
479			sum[0] += e;
480			check.sum(sum[0]);}}});
481			}
482	jsr166	1.1	}