Paul Duffin | e236301 | 2015-11-30 16:20:41 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2011 Google Inc. |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package com.google.caliper.worker; |
| 18 | |
| 19 | import static java.util.concurrent.TimeUnit.NANOSECONDS; |
| 20 | |
| 21 | import com.google.caliper.model.Measurement; |
| 22 | import com.google.caliper.model.Value; |
| 23 | import com.google.caliper.runner.InvalidBenchmarkException; |
| 24 | import com.google.caliper.runner.Running.Benchmark; |
| 25 | import com.google.caliper.runner.Running.BenchmarkMethod; |
| 26 | import com.google.caliper.util.ShortDuration; |
| 27 | import com.google.caliper.util.Util; |
| 28 | import com.google.common.annotations.VisibleForTesting; |
| 29 | import com.google.common.base.Ticker; |
| 30 | import com.google.common.collect.ImmutableSet; |
| 31 | |
| 32 | import java.lang.reflect.Method; |
| 33 | import java.util.Map; |
| 34 | import java.util.Random; |
| 35 | |
| 36 | import javax.inject.Inject; |
| 37 | |
| 38 | /** |
| 39 | * A {@link Worker} base class for micro and pico benchmarks. |
| 40 | */ |
| 41 | public abstract class RuntimeWorker extends Worker { |
| 42 | @VisibleForTesting static final int INITIAL_REPS = 100; |
| 43 | |
| 44 | protected final Random random; |
| 45 | protected final Ticker ticker; |
| 46 | protected final Options options; |
| 47 | private long totalReps; |
| 48 | private long totalNanos; |
| 49 | private long nextReps; |
| 50 | |
| 51 | RuntimeWorker(Object benchmark, |
| 52 | Method method, Random random, Ticker ticker, |
| 53 | Map<String, String> workerOptions) { |
| 54 | super(benchmark, method); |
| 55 | this.random = random; |
| 56 | // TODO(gak): investigate whether or not we can use Stopwatch |
| 57 | this.ticker = ticker; |
| 58 | this.options = new Options(workerOptions); |
| 59 | } |
| 60 | |
| 61 | @Override public void bootstrap() throws Exception { |
| 62 | totalReps = INITIAL_REPS; |
| 63 | totalNanos = invokeTimeMethod(INITIAL_REPS); |
| 64 | } |
| 65 | |
| 66 | @Override public void preMeasure(boolean inWarmup) throws Exception { |
| 67 | nextReps = calculateTargetReps(totalReps, totalNanos, options.timingIntervalNanos, |
| 68 | random.nextGaussian()); |
| 69 | if (options.gcBeforeEach && !inWarmup) { |
| 70 | Util.forceGc(); |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | @Override public Iterable<Measurement> measure() throws Exception { |
| 75 | long nanos = invokeTimeMethod(nextReps); |
| 76 | Measurement measurement = new Measurement.Builder() |
| 77 | .description("runtime") |
| 78 | .value(Value.create(nanos, "ns")) |
| 79 | .weight(nextReps) |
| 80 | .build(); |
| 81 | |
| 82 | totalReps += nextReps; |
| 83 | totalNanos += nanos; |
| 84 | return ImmutableSet.of(measurement); |
| 85 | } |
| 86 | |
| 87 | abstract long invokeTimeMethod(long reps) throws Exception; |
| 88 | |
| 89 | /** |
| 90 | * Returns a random number of reps based on a normal distribution around the estimated number of |
| 91 | * reps for the timing interval. The distribution used has a standard deviation of one fifth of |
| 92 | * the estimated number of reps. |
| 93 | */ |
| 94 | @VisibleForTesting static long calculateTargetReps(long reps, long nanos, long targetNanos, |
| 95 | double gaussian) { |
| 96 | double targetReps = (((double) reps) / nanos) * targetNanos; |
| 97 | return Math.max(1L, Math.round((gaussian * (targetReps / 5)) + targetReps)); |
| 98 | } |
| 99 | |
| 100 | /** |
| 101 | * A {@link Worker} for micro benchmarks. |
| 102 | */ |
| 103 | public static final class Micro extends RuntimeWorker { |
| 104 | @Inject Micro(@Benchmark Object benchmark, |
| 105 | @BenchmarkMethod Method method, Random random, Ticker ticker, |
| 106 | @WorkerOptions Map<String, String> workerOptions) { |
| 107 | super(benchmark, method, random, ticker, workerOptions); |
| 108 | } |
| 109 | |
| 110 | @Override long invokeTimeMethod(long reps) throws Exception { |
| 111 | int intReps = (int) reps; |
| 112 | if (reps != intReps) { |
| 113 | throw new InvalidBenchmarkException("%s.%s takes an int for reps, " |
| 114 | + "but requires a greater number to fill the given timing interval (%s). " |
| 115 | + "If this is expected (the benchmarked code is very fast), use a long parameter." |
| 116 | + "Otherwise, check your benchmark for errors.", |
| 117 | benchmark.getClass(), benchmarkMethod.getName(), |
| 118 | ShortDuration.of(options.timingIntervalNanos, NANOSECONDS)); |
| 119 | } |
| 120 | long before = ticker.read(); |
| 121 | benchmarkMethod.invoke(benchmark, intReps); |
| 122 | return ticker.read() - before; |
| 123 | } |
| 124 | } |
| 125 | |
| 126 | /** |
| 127 | * A {@link Worker} for pico benchmarks. |
| 128 | */ |
| 129 | public static final class Pico extends RuntimeWorker { |
| 130 | @Inject Pico(@Benchmark Object benchmark, |
| 131 | @BenchmarkMethod Method method, Random random, Ticker ticker, |
| 132 | @WorkerOptions Map<String, String> workerOptions) { |
| 133 | super(benchmark, method, random, ticker, workerOptions); |
| 134 | } |
| 135 | |
| 136 | @Override long invokeTimeMethod(long reps) throws Exception { |
| 137 | long before = ticker.read(); |
| 138 | benchmarkMethod.invoke(benchmark, reps); |
| 139 | return ticker.read() - before; |
| 140 | } |
| 141 | } |
| 142 | |
| 143 | private static final class Options { |
| 144 | long timingIntervalNanos; |
| 145 | boolean gcBeforeEach; |
| 146 | |
| 147 | Options(Map<String, String> optionMap) { |
| 148 | this.timingIntervalNanos = Long.parseLong(optionMap.get("timingIntervalNanos")); |
| 149 | this.gcBeforeEach = Boolean.parseBoolean(optionMap.get("gcBeforeEach")); |
| 150 | } |
| 151 | } |
| 152 | } |