test/jdk/java/nio/Buffer/SwapMicroBenchmark.java
changeset 47216 71c04702a3d5
parent 37913 3cc95b690353
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/java/nio/Buffer/SwapMicroBenchmark.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,246 @@
+/*
+ * Copyright (c) 2007, 2016, 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.
+ */
+
+/*
+ * This is not a regression test, but a micro-benchmark.
+ * To exercise swap, run with filter=LITTLE_ENDIAN on sparc,
+ * filter=BIG_ENDIAN on x86.
+ *
+ * I have run this as follows:
+ *
+ * for f in -client -server; do mergeBench dolphin . jr -dsa -da $f SwapMicroBenchmark.java filter=LITTLE_ENDIAN; done
+ *
+ * @author Martin Buchholz
+ */
+
+import java.util.*;
+import java.nio.*;
+import java.util.regex.Pattern;
+
+public class SwapMicroBenchmark {
+    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;
+    }
+
+    private static void collectAllGarbage() {
+        final java.util.concurrent.CountDownLatch drained
+            = new java.util.concurrent.CountDownLatch(1);
+        try {
+            System.gc();        // enqueue finalizable objects
+            new Object() { protected void finalize() {
+                drained.countDown(); }};
+            System.gc();        // enqueue detector
+            drained.await();    // wait for finalizer queue to drain
+            System.gc();        // cleanup finalized objects
+        } catch (InterruptedException e) { throw new Error(e); }
+    }
+
+    /**
+     * 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.
+     */
+    private static long[] time0(Job ... jobs) throws Throwable {
+        final long warmupNanos = 10L * 1000L * 1000L * 1000L;
+        long[] nanoss = new long[jobs.length];
+        for (int i = 0; i < jobs.length; i++) {
+            collectAllGarbage();
+            long t0 = System.nanoTime();
+            long t;
+            int j = 0;
+            do { jobs[i].work(); j++; }
+            while ((t = System.nanoTime() - t0) < warmupNanos);
+            nanoss[i] = t/j;
+        }
+        return nanoss;
+    }
+
+    private static void time(Job ... jobs) throws Throwable {
+
+        long[] warmup = time0(jobs); // Warm up run
+        long[] nanoss = time0(jobs); // Real timing run
+        long[] milliss = new long[jobs.length];
+        double[] ratios = new double[jobs.length];
+
+        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 < jobs.length; i++) {
+            nameWidth = Math.max(nameWidth, jobs[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 < jobs.length; i++)
+            System.out.printf(format, jobs[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 Pattern patternArg(String[] args, String keyword) {
+        String val = keywordValue(args, keyword);
+        return val == null ? null : Pattern.compile(val);
+    }
+
+    private static Job[] filter(Pattern filter, Job[] jobs) {
+        if (filter == null) return jobs;
+        Job[] newJobs = new Job[jobs.length];
+        int n = 0;
+        for (Job job : jobs)
+            if (filter.matcher(job.name()).find())
+                newJobs[n++] = job;
+        // Arrays.copyOf not available in JDK 5
+        Job[] ret = new Job[n];
+        System.arraycopy(newJobs, 0, ret, 0, n);
+        return ret;
+    }
+
+    private static void deoptimize(int sum) {
+        if (sum == 42)
+            System.out.println("the answer");
+    }
+
+    /**
+     * Usage: [iterations=N] [size=N] [filter=REGEXP]
+     */
+    public static void main(String[] args) throws Throwable {
+        final int iterations = intArg(args, "iterations", 10000);
+        final int size       = intArg(args, "size", 1024);
+        final Pattern filter = patternArg(args, "filter");
+
+        final Random rnd = new Random();
+
+        final ByteBuffer b = ByteBuffer.allocateDirect(8*size);
+        for (int i = 0; i < b.limit(); i++)
+            b.put(i, (byte) rnd.nextInt());
+
+        Job[] jobs = {
+            new Job("swap char BIG_ENDIAN") {
+                public void work() throws Throwable {
+                    b.order(ByteOrder.BIG_ENDIAN);
+                    CharBuffer x = b.asCharBuffer();
+                    for (int i = 0; i < iterations; i++) {
+                        int sum = 0;
+                        for (int j = 0, end = x.limit(); j < end; j++)
+                            sum += x.get(j);
+                        deoptimize(sum);}}},
+            new Job("swap char LITTLE_ENDIAN") {
+                public void work() throws Throwable {
+                    b.order(ByteOrder.LITTLE_ENDIAN);
+                    CharBuffer x = b.asCharBuffer();
+                    for (int i = 0; i < iterations; i++) {
+                        int sum = 0;
+                        for (int j = 0, end = x.limit(); j < end; j++)
+                            sum += x.get(j);
+                        deoptimize(sum);}}},
+            new Job("swap short BIG_ENDIAN") {
+                public void work() throws Throwable {
+                    b.order(ByteOrder.BIG_ENDIAN);
+                    ShortBuffer x = b.asShortBuffer();
+                    for (int i = 0; i < iterations; i++) {
+                        int sum = 0;
+                        for (int j = 0, end = x.limit(); j < end; j++)
+                            sum += x.get(j);
+                        deoptimize(sum);}}},
+            new Job("swap short LITTLE_ENDIAN") {
+                public void work() throws Throwable {
+                    b.order(ByteOrder.LITTLE_ENDIAN);
+                    ShortBuffer x = b.asShortBuffer();
+                    for (int i = 0; i < iterations; i++) {
+                        int sum = 0;
+                        for (int j = 0, end = x.limit(); j < end; j++)
+                            sum += x.get(j);
+                        deoptimize(sum);}}},
+            new Job("swap int BIG_ENDIAN") {
+                public void work() throws Throwable {
+                    b.order(ByteOrder.BIG_ENDIAN);
+                    IntBuffer x = b.asIntBuffer();
+                    for (int i = 0; i < iterations; i++) {
+                        int sum = 0;
+                        for (int j = 0, end = x.limit(); j < end; j++)
+                            sum += x.get(j);
+                        deoptimize(sum);}}},
+            new Job("swap int LITTLE_ENDIAN") {
+                public void work() throws Throwable {
+                    b.order(ByteOrder.LITTLE_ENDIAN);
+                    IntBuffer x = b.asIntBuffer();
+                    for (int i = 0; i < iterations; i++) {
+                        int sum = 0;
+                        for (int j = 0, end = x.limit(); j < end; j++)
+                            sum += x.get(j);
+                        deoptimize(sum);}}},
+            new Job("swap long BIG_ENDIAN") {
+                public void work() throws Throwable {
+                    b.order(ByteOrder.BIG_ENDIAN);
+                    LongBuffer x = b.asLongBuffer();
+                    for (int i = 0; i < iterations; i++) {
+                        int sum = 0;
+                        for (int j = 0, end = x.limit(); j < end; j++)
+                            sum += x.get(j);
+                        deoptimize(sum);}}},
+            new Job("swap long LITTLE_ENDIAN") {
+                public void work() throws Throwable {
+                    b.order(ByteOrder.LITTLE_ENDIAN);
+                    LongBuffer x = b.asLongBuffer();
+                    for (int i = 0; i < iterations; i++) {
+                        int sum = 0;
+                        for (int j = 0, end = x.limit(); j < end; j++)
+                            sum += x.get(j);
+                        deoptimize(sum);}}}
+        };
+
+        time(filter(filter, jobs));
+    }
+}