// from gee.cs.oswego.edu/home/jsr166/jsr166
package jsr166tests.loops;
/*
* Written by Doug Lea with assistance from members of JCP JSR-166
* Expert Group and released to the public domain, as explained at
* http://creativecommons.org/licenses/publicdomain
*/
import java.util.*;
import java.io.*;
import java.math.*;
/**
* A micro-benchmark with key types and operation mixes roughly
* corresponding to some real programs.
*
* The main results are a table of approximate nanoseconds per
* element-operation (averaged across get, put etc) for each type,
* across a range of map sizes. It also includes category "Mixed"
* that includes elements of multiple types including those with
* identical hash codes.
*
* The program includes a bunch of microbenchmarking safeguards that
* might underestimate typical performance. For example, by using many
* different key types and exercising them in warmups it disables most
* dynamic type specialization. Some test classes, like Float and
* BigDecimal are included not because they are commonly used as keys,
* but because they can be problematic for some map implementations.
*
* By default, it creates and inserts in order dense numerical keys
* and searches for keys in scrambled order. Use "s" as second arg to
* instead insert and search in unscrambled order.
*
* For String keys, the program tries to use file "testwords.txt", which
* is best used with real words. We can't check in this file, but you
* can create one from a real dictionary (1 line per word) and then run
* linux "shuf" to randomize entries. If no file exists, it uses
* String.valueOf(i) for element i.
*/
public class MapMicroBenchmark {
static final String wordFile = "testwords.txt";
static Class mapClass;
static boolean randomSearches = true;
// Nanoseconds per run
static final long NANOS_PER_JOB = 6L * 1000L*1000L*1000L;
static final long NANOS_PER_WARMUP = 100L*1000L*1000L;
// map operations per item per iteration -- change if job.work changed
static final int OPS_PER_ITER = 11;
static final int MIN_ITERS_PER_TEST = 3; // must be > 1
static final int MAX_ITERS_PER_TEST = 1000000; // avoid runaway
// sizes are at halfway points for HashMap default resizes
static final int firstSize = 9;
static final int sizeStep = 4; // each size 4X last
static final int nsizes = 9;
static final int[] sizes = new int[nsizes];
public static void main(String[] args) throws Throwable {
if (args.length == 0) {
System.out.println("Usage: java MapMicroBenchmark className [r|s]keys [r|s]searches");
return;
}
mapClass = Class.forName(args[0]);
if (args.length > 1) {
if (args[1].startsWith("s"))
randomSearches = false;
else if (args[1].startsWith("r"))
randomSearches = true;
}
System.out.print("Class " + mapClass.getName());
if (randomSearches)
System.out.print(" randomized searches");
else
System.out.print(" sequential searches");
System.out.println();
int n = firstSize;
for (int i = 0; i < nsizes - 1; ++i) {
sizes[i] = n;
n *= sizeStep;
}
sizes[nsizes - 1] = n;
int njobs = 10;
Job[] jobs = new Job[njobs];
Object[] os = new Object[n];
for (int i = 0; i < n; i++) os[i] = new Object();
jobs[0] = new Job("Object ", os, Object.class);
Object[] ss = new Object[n];
initStringKeys(ss, n);
jobs[1] = new Job("String ", ss, String.class);
Object[] is = new Object[n];
for (int i = 0; i < n; i++) is[i] = Integer.valueOf(i);
jobs[2] = new Job("Integer ", is, Integer.class);
Object[] ls = new Object[n];
for (int i = 0; i < n; i++) ls[i] = Long.valueOf((long) i);
jobs[3] = new Job("Long ", ls, Long.class);
Object[] fs = new Object[n];
for (int i = 0; i < n; i++) fs[i] = Float.valueOf((float) i);
jobs[4] = new Job("Float ", fs, Float.class);
Object[] ds = new Object[n];
for (int i = 0; i < n; i++) ds[i] = Double.valueOf((double) i);
jobs[5] = new Job("Double ", ds, Double.class);
Object[] bs = new Object[n];
long b = -n; // include some negatives
for (int i = 0; i < n; i++) bs[i] = BigInteger.valueOf(b += 3);
jobs[6] = new Job("BigInteger", bs, BigInteger.class);
Object[] es = new Object[n];
long d = Integer.MAX_VALUE; // include crummy codes
for (int i = 0; i < n; i++) es[i] = BigDecimal.valueOf(d += 65536);
jobs[7] = new Job("BigDecimal", es, BigDecimal.class);
Object[] rs = new Object[n];
for (int i = 0; i < n; i++) rs[i] = new RandomInt();
jobs[8] = new Job("RandomInt ", rs, RandomInt.class);
Object[] ms = new Object[n];
for (int i = 0; i < n; i += 2) {
int r = rng.nextInt(njobs - 1);
ms[i] = jobs[r].items[i];
// include some that will have same hash but not .equal
if (++r >= njobs - 1) r = 0;
ms[i+1] = jobs[r].items[i];
}
jobs[9] = new Job("Mixed ", ms, Object.class);
Job mixed = jobs[9];
warmup1(mixed);
warmup2(jobs);
warmup1(mixed);
warmup3(jobs);
Thread.sleep(500);
time(jobs);
}
static void runWork(Job[] jobs, int minIters, int maxIters, long timeLimit) throws Throwable {
for (int k = 0; k < nsizes; ++k) {
int len = sizes[k];
for (int i = 0; i < jobs.length; i++) {
Thread.sleep(50);
jobs[i].nanos[k] = jobs[i].work(len, minIters, maxIters, timeLimit);
System.out.print(".");
}
}
System.out.println();
}
// First warmup -- run only mixed job to discourage type specialization
static void warmup1(Job job) throws Throwable {
for (int k = 0; k < nsizes; ++k)
job.work(sizes[k], 1, 1, 0);
}
// Second, run each once
static void warmup2(Job[] jobs) throws Throwable {
System.out.print("warm up");
runWork(jobs, 1, 1, 0);
long ck = jobs[0].checkSum;
for (int i = 1; i < jobs.length - 1; i++) {
if (jobs[i].checkSum != ck)
throw new Error("CheckSum");
}
}
// Third: short timed runs
static void warmup3(Job[] jobs) throws Throwable {
System.out.print("warm up");
runWork(jobs, 1, MAX_ITERS_PER_TEST, NANOS_PER_WARMUP);
}
static void time(Job[] jobs) throws Throwable {
System.out.print("running");
runWork(jobs, MIN_ITERS_PER_TEST, MAX_ITERS_PER_TEST, NANOS_PER_JOB);
System.out.print("Type/Size:");
for (int k = 0; k < nsizes; ++k)
System.out.printf("%7d", sizes[k]);
System.out.println();
long[] aves = new long[nsizes];
int njobs = jobs.length;
for (int i = 0; i < njobs; i++) {
System.out.print(jobs[i].name);
for (int k = 0; k < nsizes; ++k) {
long nanos = jobs[i].nanos[k];
System.out.printf("%7d", nanos);
aves[k] += nanos;
}
System.out.println();
}
System.out.println();
System.out.print("average ");
for (int k = 0; k < nsizes; ++k)
System.out.printf("%7d", (aves[k] / njobs));
System.out.println("\n");
}
static final class Job {
final String name;
final Class elementClass;
long[] nanos = new long[nsizes];
final Object[] items;
Object[] searches;
volatile long checkSum;
volatile int lastSum;
Job(String name, Object[] items, Class elementClass) {
this.name = name;
this.items = items;
this.elementClass = elementClass;
if (randomSearches) {
scramble(items);
this.searches = new Object[items.length];
System.arraycopy(items, 0, searches, 0, items.length);
scramble(searches);
}
else
this.searches = items;
}
public long work(int len, int minIters, int maxIters, long timeLimit) {
Map m;
try {
m = (Map) mapClass.newInstance();
} catch (Exception e) {
throw new RuntimeException("Can't instantiate " + mapClass + ": " + e);
}
Object[] ins = items;
Object[] keys = searches;
if (ins.length < len || keys.length < len)
throw new Error(name);
int half = len / 2;
int quarter = half / 2;
int sum = lastSum;
long startTime = System.nanoTime();
long elapsed;
int j = 0;
for (;;) {
for (int i = 0; i < half; ++i) {
Object x = ins[i];
if (m.put(x, x) == null)
++sum;
}
checkSum += sum ^ (sum << 1); // help avoid loop merging
sum += len - half;
for (int i = 0; i < len; ++i) {
Object x = keys[i];
Object v = m.get(x);
if (elementClass.isInstance(v)) // touch v
++sum;
}
checkSum += sum ^ (sum << 2);
for (int i = half; i < len; ++i) {
Object x = ins[i];
if (m.put(x, x) == null)
++sum;
}
checkSum += sum ^ (sum << 3);
for (Object e : m.keySet()) {
if (elementClass.isInstance(e))
++sum;
}
checkSum += sum ^ (sum << 4);
for (Object e : m.values()) {
if (elementClass.isInstance(e))
++sum;
}
checkSum += sum ^ (sum << 5);
for (int i = len - 1; i >= 0; --i) {
Object x = keys[i];
Object v = m.get(x);
if (elementClass.isInstance(v))
++sum;
}
checkSum += sum ^ (sum << 6);
for (int i = 0; i < len; ++i) {
Object x = ins[i];
Object v = m.get(x);
if (elementClass.isInstance(v))
++sum;
}
checkSum += sum ^ (sum << 7);
for (int i = 0; i < len; ++i) {
Object x = keys[i];
Object v = ins[i];
if (m.put(x, v) == x)
++sum;
}
checkSum += sum ^ (sum << 8);
for (int i = 0; i < len; ++i) {
Object x = keys[i];
Object v = ins[i];
if (v == m.get(x))
++sum;
}
checkSum += sum ^ (sum << 9);
for (int i = len - 1; i >= 0; --i) {
Object x = ins[i];
Object v = m.get(x);
if (elementClass.isInstance(v))
++sum;
}
checkSum += sum ^ (sum << 10);
for (int i = len - 1; i >= 0; --i) {
Object x = keys[i];
Object v = ins[i];
if (v == m.get(x))
++sum;
}
checkSum += sum ^ (sum << 11);
for (int i = 0; i < quarter; ++i) {
Object x = keys[i];
if (m.remove(x) != null)
++sum;
}
for (int i = 0; i < quarter; ++i) {
Object x = keys[i];
if (m.put(x, x) == null)
++sum;
}
m.clear();
sum += len - (quarter * 2);
checkSum += sum ^ (sum << 12);
if (j == 0 && sum != lastSum + len * OPS_PER_ITER)
throw new Error(name);
elapsed = System.nanoTime() - startTime;
++j;
if (j >= minIters &&
(j >= maxIters || elapsed >= timeLimit))
break;
// non-warmup - swap some keys for next insert
if (minIters != 1 && randomSearches)
shuffleSome(ins, len, len >>> 3);
}
long ops = ((long) j) * len * OPS_PER_ITER;
lastSum = sum;
return elapsed / ops;
}
}
static final Random rng = new Random(3122688);
// Shuffle the subarrays for each size. This doesn't fully
// randomize, but the remaining partial locality is arguably a bit
// more realistic
static void scramble(Object[] a) {
for (int k = 0; k < sizes.length; ++k) {
int origin = (k == 0) ? 0 : sizes[k-1];
for (int i = sizes[k]; i > origin + 1; i--) {
Object t = a[i-1];
int r = rng.nextInt(i - origin) + origin;
a[i-1] = a[r];
a[r] = t;
}
}
}
// plain array shuffle
static void shuffle(Object[] a, int size) {
for (int i= size; i>1; i--) {
Object t = a[i-1];
int r = rng.nextInt(i);
a[i-1] = a[r];
a[r] = t;
}
}
// swap nswaps elements
static void shuffleSome(Object[] a, int size, int nswaps) {
for (int s = 0; s < nswaps; ++s) {
int i = rng.nextInt(size);
int r = rng.nextInt(size);
Object t = a[i];
a[i] = a[r];
a[r] = t;
}
}
// Integer-like class with random hash codes
static final class RandomInt {
static int seed = 3122688;
static int next() { // a non-xorshift, 2^32-period RNG
int x = seed;
int lo = 16807 * (x & 0xFFFF);
int hi = 16807 * (x >>> 16);
lo += (hi & 0x7FFF) << 16;
if ((lo & 0x80000000) != 0) {
lo &= 0x7fffffff;
++lo;
}
lo += hi >>> 15;
if (lo == 0 || (lo & 0x80000000) != 0) {
lo &= 0x7fffffff;
++lo;
}
seed = lo;
return x;
}
final int value;
RandomInt() { value = next(); }
public int hashCode() { return value; }
public boolean equals(Object x) {
return (x instanceof RandomInt) && ((RandomInt)x).value == value;
}
}
// Read in String keys from file if possible
static void initStringKeys(Object[] keys, int n) throws Exception {
FileInputStream fr = null;
try {
fr = new FileInputStream(wordFile);
} catch (IOException ex) {
System.out.println("No word file. Using String.valueOf(i)");
for (int i = 0; i < n; i++)
keys[i] = String.valueOf(i);
return;
}
BufferedInputStream in = new BufferedInputStream(fr);
int k = 0;
outer:while (k < n) {
StringBuffer sb = new StringBuffer();
for (;;) {
int c = in.read();
if (c < 0)
break outer;
char ch = (char) c;
if (ch == '\n') {
keys[k++] = sb.toString();
break;
}
if (!Character.isWhitespace(ch))
sb.append(ch);
}
}
in.close();
// fill up remaining keys with path-like compounds of previous pairs
int j = 0;
while (k < n)
keys[k++] = (String) keys[j++] + "/" + (String) keys[j];
}
}