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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/licenses/publicdomain |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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import java.util.*; |
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import java.io.*; |
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import java.math.*; |
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/** |
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* A micro-benchmark with key types and operation mixes roughly |
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* corresponding to some real programs. |
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* |
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* |
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* The main results are a table of approximate nanoseconds per |
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* element-operation (averaged across get, put etc) for each type, |
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* across a range of map sizes. |
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* across a range of map sizes. It also includes category "Mixed" |
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* that includes elements of multiple types including those with |
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* identical hash codes. |
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* |
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* The program includes a bunch of microbenchmarking safeguards that |
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* might underestimate typical performance. For example, by using many |
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* dynamic type specialization. Some test classes, like Float and |
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* BigDecimal are included not because they are commonly used as keys, |
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* but because they can be problematic for some map implementations. |
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* |
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* |
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* By default, it creates and inserts in order dense numerical keys |
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* and searches for keys in scrambled order. Use "r" as second arg to |
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* instead use random numerical values, and "s" as third arg to search |
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* in insertion order. |
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* and searches for keys in scrambled order. Use "s" as second arg to |
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* instead insert and search in unscrambled order. |
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* |
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* For String keys, the program tries to use file "testwords.txt", which |
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* is best used with real words. We can't check in this file, but you |
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* can create one from a real dictionary (1 line per word) and then run |
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* linux "shuf" to randomize entries. If no file exists, it uses |
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* String.valueOf(i) for element i. |
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*/ |
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public class MapMicroBenchmark { |
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static final String wordFile = "testwords.txt"; |
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|
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static Class mapClass; |
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static boolean randomSearches = true; |
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static boolean randomKeys = false; |
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|
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static final long NANOS_PER_JOB = 8L * 1000L*1000L*1000L; |
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// Nanoseconds per run |
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static final long NANOS_PER_JOB = 6L * 1000L*1000L*1000L; |
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static final long NANOS_PER_WARMUP = 100L*1000L*1000L; |
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|
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// map operations per item per iteration -- change if job.work changed |
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static final int OPS_PER_ITER = 11; |
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static final int MIN_ITERS_PER_TEST = 2; |
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static final int MAX_ITERS_PER_TEST = 1000000; |
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static final int MIN_ITERS_PER_TEST = 3; // must be > 1 |
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static final int MAX_ITERS_PER_TEST = 1000000; // avoid runaway |
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|
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// sizes are at halfway points for HashMap default resizes |
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static final int firstSize = 36; |
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static final int firstSize = 9; |
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static final int sizeStep = 4; // each size 4X last |
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static final int nsizes = 8; |
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static final int nsizes = 9; |
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static final int[] sizes = new int[nsizes]; |
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|
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static final class Missing {} // class for guaranteed non-matches |
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static final Object MISSING = new Missing(); |
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|
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static Map newMap() { |
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try { |
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return (Map)mapClass.newInstance(); |
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} catch(Exception e) { |
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throw new RuntimeException("Can't instantiate " + mapClass + ": " + e); |
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} |
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} |
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|
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public static void main(String[] args) throws Throwable { |
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if (args.length == 0) { |
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System.out.println("Usage: java MapMicroBenchmark className [r|s]keys [r|s]searches"); |
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return; |
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} |
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|
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mapClass = Class.forName(args[0]); |
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|
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if (args.length > 1) { |
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if (args[1].startsWith("s")) |
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randomKeys = false; |
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else if (args[1].startsWith("r")) |
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randomKeys = true; |
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} |
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if (args.length > 2) { |
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if (args[2].startsWith("s")) |
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randomSearches = false; |
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else if (args[2].startsWith("r")) |
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else if (args[1].startsWith("r")) |
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randomSearches = true; |
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} |
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|
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System.out.print("Class " + mapClass.getName()); |
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if (randomKeys) |
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System.out.print(" random keys"); |
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else |
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System.out.print(" sequential keys"); |
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if (randomSearches) |
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System.out.print(" randomized searches"); |
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else |
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} |
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sizes[nsizes - 1] = n; |
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|
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Object[] ss = new Object[n]; |
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int njobs = 10; |
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Job[] jobs = new Job[njobs]; |
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|
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Object[] os = new Object[n]; |
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for (int i = 0; i < n; i++) os[i] = new Object(); |
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jobs[0] = new Job("Object ", os, Object.class); |
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|
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Object[] ss = new Object[n]; |
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initStringKeys(ss, n); |
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jobs[1] = new Job("String ", ss, String.class); |
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|
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Object[] is = new Object[n]; |
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for (int i = 0; i < n; i++) is[i] = Integer.valueOf(i); |
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jobs[2] = new Job("Integer ", is, Integer.class); |
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|
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Object[] ls = new Object[n]; |
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for (int i = 0; i < n; i++) ls[i] = Long.valueOf((long) i); |
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jobs[3] = new Job("Long ", ls, Long.class); |
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|
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Object[] fs = new Object[n]; |
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for (int i = 0; i < n; i++) fs[i] = Float.valueOf((float) i); |
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jobs[4] = new Job("Float ", fs, Float.class); |
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|
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Object[] ds = new Object[n]; |
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for (int i = 0; i < n; i++) ds[i] = Double.valueOf((double) i); |
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jobs[5] = new Job("Double ", ds, Double.class); |
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|
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Object[] bs = new Object[n]; |
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Object[] es = new Object[n]; |
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long b = -n; // include some negatives |
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for (int i = 0; i < n; i++) bs[i] = BigInteger.valueOf(b += 3); |
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jobs[6] = new Job("BigInteger", bs, BigInteger.class); |
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|
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// To guarantee uniqueness, use xorshift for "random" versions |
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int j = randomKeys? 1234567 : 0; |
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for (int i = 0; i < n; i++) { |
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ss[i] = String.valueOf(j); |
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os[i] = new Object(); |
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is[i] = Integer.valueOf(j); |
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ls[i] = Long.valueOf((long)j); |
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fs[i] = Float.valueOf((float)i); // can't use random for float |
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ds[i] = Double.valueOf((double)j); |
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bs[i] = BigInteger.valueOf(j); |
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es[i] = BigDecimal.valueOf(j); |
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j = randomKeys? xorshift(j) : j + 1; |
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} |
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|
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List<Job> list = new ArrayList<Job>(); |
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list.add(new Job("BigDecimal", es)); |
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list.add(new Job("BigInteger", bs)); |
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list.add(new Job("String ", ss)); |
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list.add(new Job("Double ", ds)); |
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list.add(new Job("Float ", fs)); |
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list.add(new Job("Long ", ls)); |
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list.add(new Job("Integer ", is)); |
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list.add(new Job("Object ", os)); |
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|
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Job[] jobs = list.toArray(new Job[0]); |
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warmup(jobs); |
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warmup(jobs); |
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time(jobs); |
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Object[] es = new Object[n]; |
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long d = Integer.MAX_VALUE; // include crummy codes |
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for (int i = 0; i < n; i++) es[i] = BigDecimal.valueOf(d += 65536); |
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jobs[7] = new Job("BigDecimal", es, BigDecimal.class); |
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|
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Object[] rs = new Object[n]; |
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for (int i = 0; i < n; i++) rs[i] = new RandomInt(); |
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jobs[8] = new Job("RandomInt ", rs, RandomInt.class); |
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|
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Object[] ms = new Object[n]; |
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for (int i = 0; i < n; i += 2) { |
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int r = rng.nextInt(njobs - 1); |
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ms[i] = jobs[r].items[i]; |
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// include some that will have same hash but not .equal |
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if (++r >= njobs - 1) r = 0; |
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ms[i+1] = jobs[r].items[i]; |
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} |
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jobs[9] = new Job("Mixed ", ms, Object.class); |
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Job mixed = jobs[9]; |
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|
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warmup1(mixed); |
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warmup2(jobs); |
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warmup1(mixed); |
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warmup3(jobs); |
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Thread.sleep(500); |
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time(jobs); |
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} |
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|
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static void runWork(Job[] jobs, int maxIters) throws Throwable { |
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for (int k = 0; k < nsizes; ++k) { |
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static void runWork(Job[] jobs, int minIters, int maxIters, long timeLimit) throws Throwable { |
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for (int k = 0; k < nsizes; ++k) { |
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int len = sizes[k]; |
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for (int i = 0; i < jobs.length; i++) { |
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jobs[i].setup(len); |
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Thread.sleep(50); |
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jobs[i].nanos[k] = jobs[i].work(len, maxIters); |
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jobs[i].nanos[k] = jobs[i].work(len, minIters, maxIters, timeLimit); |
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System.out.print("."); |
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} |
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} |
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System.out.println(); |
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} |
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|
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static void warmup(Job[] jobs) throws Throwable { |
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// First warmup -- run only mixed job to discourage type specialization |
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static void warmup1(Job job) throws Throwable { |
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for (int k = 0; k < nsizes; ++k) |
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job.work(sizes[k], 1, 1, 0); |
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} |
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|
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// Second, run each once |
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static void warmup2(Job[] jobs) throws Throwable { |
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System.out.print("warm up"); |
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runWork(jobs, MIN_ITERS_PER_TEST); |
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runWork(jobs, 1, 1, 0); |
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long ck = jobs[0].checkSum; |
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for (int i = 1; i < jobs.length; i++) { |
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for (int i = 1; i < jobs.length - 1; i++) { |
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if (jobs[i].checkSum != ck) |
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throw new Error("CheckSum"); |
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} |
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} |
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|
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// Third: short timed runs |
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static void warmup3(Job[] jobs) throws Throwable { |
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System.out.print("warm up"); |
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runWork(jobs, 1, MAX_ITERS_PER_TEST, NANOS_PER_WARMUP); |
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} |
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|
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static void time(Job[] jobs) throws Throwable { |
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System.out.print("running"); |
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runWork(jobs, MAX_ITERS_PER_TEST); |
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runWork(jobs, MIN_ITERS_PER_TEST, MAX_ITERS_PER_TEST, NANOS_PER_JOB); |
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|
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System.out.print("Type/Size:"); |
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for (int k = 0; k < nsizes; ++k) |
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System.out.printf("%8d", sizes[k]); |
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System.out.printf("%7d", sizes[k]); |
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System.out.println(); |
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|
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long[] aves = new long[nsizes]; |
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int njobs = jobs.length; |
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|
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for (int i = 0; i < njobs; i++) { |
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for (int i = 0; i < njobs; i++) { |
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System.out.print(jobs[i].name); |
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for (int k = 0; k < nsizes; ++k) { |
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long nanos = jobs[i].nanos[k]; |
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System.out.printf("%8d", nanos); |
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System.out.printf("%7d", nanos); |
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aves[k] += nanos; |
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} |
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System.out.println(); |
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System.out.println(); |
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System.out.print("average "); |
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for (int k = 0; k < nsizes; ++k) |
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System.out.printf("%8d", (aves[k] / njobs)); |
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System.out.println(); |
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System.out.printf("%7d", (aves[k] / njobs)); |
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System.out.println("\n"); |
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} |
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|
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|
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static final class Job { |
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final String name; |
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final String name; |
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> |
final Class elementClass; |
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long[] nanos = new long[nsizes]; |
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final Object[] items; |
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final Object[] dups; |
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Object[] reordered; |
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> |
Object[] searches; |
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volatile long checkSum; |
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volatile int lastSum; |
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Job(String name, Object[] items) { |
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Job(String name, Object[] items, Class elementClass) { |
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this.name = name; |
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this.items = items; |
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if (randomSearches) |
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this.dups = new Object[items.length]; |
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else |
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this.dups = items; |
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} |
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|
208 |
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public void setup(int len) { |
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this.elementClass = elementClass; |
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if (randomSearches) { |
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System.arraycopy(items, 0, dups, 0, len); |
228 |
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shuffle(dups, len); |
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< |
reordered = dups; |
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scramble(items); |
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this.searches = new Object[items.length]; |
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System.arraycopy(items, 0, searches, 0, items.length); |
230 |
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scramble(searches); |
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} |
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else |
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reordered = items; |
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this.searches = items; |
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} |
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|
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public long work(int len, int maxIters) { |
236 |
> |
public long work(int len, int minIters, int maxIters, long timeLimit) { |
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> |
Map m; |
238 |
> |
try { |
239 |
> |
m = (Map) mapClass.newInstance(); |
240 |
> |
} catch (Exception e) { |
241 |
> |
throw new RuntimeException("Can't instantiate " + mapClass + ": " + e); |
242 |
> |
} |
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Object[] ins = items; |
244 |
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Object[] keys = reordered; |
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> |
Object[] keys = searches; |
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|
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if (ins.length < len || keys.length < len) |
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throw new Error(name); |
248 |
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int half = len / 2; |
249 |
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Class eclass = ins[0].getClass(); |
249 |
> |
int quarter = half / 2; |
250 |
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int sum = lastSum; |
251 |
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long startTime = System.nanoTime(); |
252 |
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long elapsed; |
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Map m = newMap(); |
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int j = 0; |
254 |
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for (;;) { |
255 |
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for (int i = 0; i < half; ++i) { |
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++sum; |
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} |
260 |
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checkSum += sum ^ (sum << 1); // help avoid loop merging |
261 |
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sum += len - half; |
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for (int i = 0; i < len; ++i) { |
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Object x = keys[i]; |
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Object v = m.get(x); |
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< |
if (v != null && v.getClass() == eclass) // touch v |
266 |
< |
sum += 2; |
264 |
> |
Object v = m.get(x); |
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> |
if (elementClass.isInstance(v)) // touch v |
266 |
> |
++sum; |
267 |
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} |
268 |
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checkSum += sum ^ (sum << 2); |
269 |
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for (int i = half; i < len; ++i) { |
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} |
274 |
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checkSum += sum ^ (sum << 3); |
275 |
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for (Object e : m.keySet()) { |
276 |
< |
if (e.getClass() == eclass) |
276 |
> |
if (elementClass.isInstance(e)) |
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++sum; |
278 |
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} |
279 |
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checkSum += sum ^ (sum << 4); |
280 |
|
for (Object e : m.values()) { |
281 |
< |
if (e.getClass() == eclass) |
281 |
> |
if (elementClass.isInstance(e)) |
282 |
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++sum; |
283 |
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} |
284 |
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checkSum += sum ^ (sum << 5); |
285 |
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for (int i = len - 1; i >= 0; --i) { |
286 |
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Object x = keys[i]; |
287 |
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Object v = m.get(x); |
288 |
< |
if (v != null && v.getClass() == eclass) |
288 |
> |
if (elementClass.isInstance(v)) |
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|
++sum; |
290 |
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} |
291 |
|
checkSum += sum ^ (sum << 6); |
292 |
|
for (int i = 0; i < len; ++i) { |
293 |
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Object x = ins[i]; |
294 |
|
Object v = m.get(x); |
295 |
< |
if (v != null && v.getClass() == eclass) |
295 |
> |
if (elementClass.isInstance(v)) |
296 |
|
++sum; |
297 |
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} |
298 |
|
checkSum += sum ^ (sum << 7); |
306 |
|
for (int i = 0; i < len; ++i) { |
307 |
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Object x = keys[i]; |
308 |
|
Object v = ins[i]; |
309 |
< |
if (v.equals(m.get(x))) |
309 |
> |
if (v == m.get(x)) |
310 |
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++sum; |
311 |
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} |
312 |
|
checkSum += sum ^ (sum << 9); |
313 |
|
for (int i = len - 1; i >= 0; --i) { |
314 |
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Object x = ins[i]; |
315 |
< |
if (m.get(x) != MISSING) |
315 |
> |
Object v = m.get(x); |
316 |
> |
if (elementClass.isInstance(v)) |
317 |
|
++sum; |
318 |
|
} |
319 |
|
checkSum += sum ^ (sum << 10); |
320 |
|
for (int i = len - 1; i >= 0; --i) { |
321 |
|
Object x = keys[i]; |
322 |
|
Object v = ins[i]; |
323 |
< |
if (v.equals(m.get(x))) |
323 |
> |
if (v == m.get(x)) |
324 |
|
++sum; |
325 |
|
} |
326 |
|
checkSum += sum ^ (sum << 11); |
327 |
< |
if ((j & 1) == 1) { // lower remove rate |
328 |
< |
for (int i = 0; i < len; ++i) { |
329 |
< |
Object x = keys[i]; |
330 |
< |
if (m.remove(x) != null) |
331 |
< |
++sum; |
332 |
< |
} |
333 |
< |
} |
334 |
< |
else { |
335 |
< |
m.clear(); |
311 |
< |
sum += len; |
327 |
> |
for (int i = 0; i < quarter; ++i) { |
328 |
> |
Object x = keys[i]; |
329 |
> |
if (m.remove(x) != null) |
330 |
> |
++sum; |
331 |
> |
} |
332 |
> |
for (int i = 0; i < quarter; ++i) { |
333 |
> |
Object x = keys[i]; |
334 |
> |
if (m.put(x, x) == null) |
335 |
> |
++sum; |
336 |
|
} |
337 |
+ |
/* // uncomment to avoid calling clear() |
338 |
+ |
for (int i = 0; i < len; ++i) { |
339 |
+ |
Object x = keys[i]; |
340 |
+ |
m.remove(x); |
341 |
+ |
} |
342 |
+ |
*/ |
343 |
+ |
m.clear(); |
344 |
+ |
sum += len - (quarter * 2); |
345 |
|
checkSum += sum ^ (sum << 12); |
346 |
|
|
347 |
+ |
if (j == 0 && sum != lastSum + len * OPS_PER_ITER) |
348 |
+ |
throw new Error(name); |
349 |
+ |
|
350 |
|
elapsed = System.nanoTime() - startTime; |
351 |
|
++j; |
352 |
< |
if (j >= MIN_ITERS_PER_TEST && |
353 |
< |
(j >= maxIters || elapsed >= NANOS_PER_JOB)) |
352 |
> |
if (j >= minIters && |
353 |
> |
(j >= maxIters || elapsed >= timeLimit)) |
354 |
|
break; |
355 |
+ |
// non-warmup - swap some keys for next insert |
356 |
+ |
if (minIters != 1 && randomSearches) |
357 |
+ |
shuffleSome(ins, len, len >>> 3); |
358 |
|
} |
359 |
< |
long ops = ((long)j) * len * OPS_PER_ITER; |
322 |
< |
if (sum != lastSum + (int)ops) |
323 |
< |
throw new Error(name); |
359 |
> |
long ops = ((long) j) * len * OPS_PER_ITER; |
360 |
|
lastSum = sum; |
361 |
|
return elapsed / ops; |
362 |
|
} |
363 |
|
|
364 |
|
} |
365 |
|
|
330 |
– |
static final int xorshift(int seed) { |
331 |
– |
seed ^= seed << 1; |
332 |
– |
seed ^= seed >>> 3; |
333 |
– |
seed ^= seed << 10; |
334 |
– |
return seed; |
335 |
– |
} |
366 |
|
|
367 |
+ |
static final Random rng = new Random(3122688); |
368 |
|
|
369 |
< |
static final Random rng = new Random(3152688); |
369 |
> |
// Shuffle the subarrays for each size. This doesn't fully |
370 |
> |
// randomize, but the remaining partial locality is arguably a bit |
371 |
> |
// more realistic |
372 |
> |
static void scramble(Object[] a) { |
373 |
> |
for (int k = 0; k < sizes.length; ++k) { |
374 |
> |
int origin = (k == 0) ? 0 : sizes[k-1]; |
375 |
> |
for (int i = sizes[k]; i > origin + 1; i--) { |
376 |
> |
Object t = a[i-1]; |
377 |
> |
int r = rng.nextInt(i - origin) + origin; |
378 |
> |
a[i-1] = a[r]; |
379 |
> |
a[r] = t; |
380 |
> |
} |
381 |
> |
} |
382 |
> |
} |
383 |
|
|
384 |
+ |
// plain array shuffle |
385 |
|
static void shuffle(Object[] a, int size) { |
386 |
|
for (int i= size; i>1; i--) { |
387 |
|
Object t = a[i-1]; |
391 |
|
} |
392 |
|
} |
393 |
|
|
394 |
< |
} |
394 |
> |
// swap nswaps elements |
395 |
> |
static void shuffleSome(Object[] a, int size, int nswaps) { |
396 |
> |
for (int s = 0; s < nswaps; ++s) { |
397 |
> |
int i = rng.nextInt(size); |
398 |
> |
int r = rng.nextInt(size); |
399 |
> |
Object t = a[i]; |
400 |
> |
a[i] = a[r]; |
401 |
> |
a[r] = t; |
402 |
> |
} |
403 |
> |
} |
404 |
|
|
405 |
+ |
// Integer-like class with random hash codes |
406 |
+ |
static final class RandomInt { |
407 |
+ |
static int seed = 3122688; |
408 |
+ |
static int next() { // a non-xorshift, 2^32-period RNG |
409 |
+ |
int x = seed; |
410 |
+ |
int lo = 16807 * (x & 0xFFFF); |
411 |
+ |
int hi = 16807 * (x >>> 16); |
412 |
+ |
lo += (hi & 0x7FFF) << 16; |
413 |
+ |
if ((lo & 0x80000000) != 0) { |
414 |
+ |
lo &= 0x7fffffff; |
415 |
+ |
++lo; |
416 |
+ |
} |
417 |
+ |
lo += hi >>> 15; |
418 |
+ |
if (lo == 0 || (lo & 0x80000000) != 0) { |
419 |
+ |
lo &= 0x7fffffff; |
420 |
+ |
++lo; |
421 |
+ |
} |
422 |
+ |
seed = lo; |
423 |
+ |
return x; |
424 |
+ |
} |
425 |
+ |
final int value; |
426 |
+ |
RandomInt() { value = next(); } |
427 |
+ |
public int hashCode() { return value; } |
428 |
+ |
public boolean equals(Object x) { |
429 |
+ |
return (x instanceof RandomInt) && ((RandomInt)x).value == value; |
430 |
+ |
} |
431 |
+ |
} |
432 |
+ |
|
433 |
+ |
// Read in String keys from file if possible |
434 |
+ |
static void initStringKeys(Object[] keys, int n) throws Exception { |
435 |
+ |
FileInputStream fr = null; |
436 |
+ |
try { |
437 |
+ |
fr = new FileInputStream(wordFile); |
438 |
+ |
} catch (IOException ex) { |
439 |
+ |
System.out.println("No word file. Using String.valueOf(i)"); |
440 |
+ |
for (int i = 0; i < n; i++) |
441 |
+ |
keys[i] = String.valueOf(i); |
442 |
+ |
return; |
443 |
+ |
} |
444 |
+ |
|
445 |
+ |
BufferedInputStream in = new BufferedInputStream(fr); |
446 |
+ |
int k = 0; |
447 |
+ |
outer:while (k < n) { |
448 |
+ |
StringBuffer sb = new StringBuffer(); |
449 |
+ |
for (;;) { |
450 |
+ |
int c = in.read(); |
451 |
+ |
if (c < 0) |
452 |
+ |
break outer; |
453 |
+ |
char ch = (char) c; |
454 |
+ |
if (ch == '\n') { |
455 |
+ |
keys[k++] = sb.toString(); |
456 |
+ |
break; |
457 |
+ |
} |
458 |
+ |
if (!Character.isWhitespace(ch)) |
459 |
+ |
sb.append(ch); |
460 |
+ |
} |
461 |
+ |
} |
462 |
+ |
in.close(); |
463 |
+ |
|
464 |
+ |
// fill up remaining keys with path-like compounds of previous pairs |
465 |
+ |
int j = 0; |
466 |
+ |
while (k < n) |
467 |
+ |
keys[k++] = (String) keys[j++] + "/" + (String) keys[j]; |
468 |
+ |
} |
469 |
+ |
|
470 |
+ |
} |