BufferTest.java Source code

Introduction

Here is the source code for BufferTest.java

Source

//package com.ryanm.util;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.util.Random;

/**
 * @author ryanm
 */
public class BufferTest {
    private ByteBuffer bb;

    private FloatBuffer floats;

    private float[] data;

    /**
     * @param args
     */
    public static void main(String[] args) {
        new BufferTest().run();
    }

    private void run() {
        final int size = 100000;

        bb = ByteBuffer.allocateDirect(4 * size).order(ByteOrder.nativeOrder());
        floats = bb.asFloatBuffer();

        data = data(size);

        System.out.println("# size\tsingle\tindexed\tbatch");

        int base = 0;

        int e = size;
        while (base + e > 100) {
            test(base + e);
            e /= 2;
        }
    }

    private void test(int elements) {
        int time = 1000;

        System.out.print(elements + "\t");
        long kbps = singlePut(data, elements, floats, time);
        System.out.print(kbps + "\t");
        kbps = singleIndexedPut(data, elements, floats, time);
        System.out.print(kbps + "\t");
        kbps = bulkPut(data, elements, floats, time);
        System.out.println(kbps + "\t");
    }

    private long singlePut(float[] data, int elements, FloatBuffer target, int testTime) {
        long start = System.currentTimeMillis();
        long elapsed = 0;
        int reps = 0;

        target.clear();

        do {
            for (int i = 0; i < elements; i++) {
                target.put(data[i]);
            }
            target.flip();
            reps++;
            elapsed = System.currentTimeMillis() - start;
        } while (elapsed < testTime);

        long bytes = (long) elements * (long) reps * 4;

        return bytes / elapsed / 1024;
    }

    private long singleIndexedPut(float[] data, int elements, FloatBuffer target, int testTime) {
        long start = System.currentTimeMillis();
        long elapsed = 0;
        int reps = 0;

        target.clear();

        do {
            for (int i = 0; i < elements; i++) {
                target.put(i, data[i]);
            }
            reps++;
            elapsed = System.currentTimeMillis() - start;
        } while (elapsed < testTime);

        long bytes = (long) elements * (long) reps * 4;

        return bytes / elapsed / 1024;
    }

    private long bulkPut(float[] data, int elements, FloatBuffer target, int testTime) {
        long start = System.currentTimeMillis();
        long elapsed = 0;
        int reps = 0;

        target.clear();

        do {
            target.put(data, 0, elements);
            target.flip();

            reps++;
            elapsed = System.currentTimeMillis() - start;
        } while (elapsed < testTime);

        long bytes = (long) elements * (long) reps * 4;

        return bytes / elapsed / 1024;
    }

    private float[] data(int elements) {
        float[] data = new float[elements];
        Random rng = new Random();

        for (int i = 0; i < data.length; i++) {
            data[i] = 100 * rng.nextFloat();
        }

        return data;
    }
}