| /* |
| * Copyright (C) 2014 The Guava Authors |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.google.common.util.concurrent; |
| |
| import static com.google.common.collect.Iterables.cycle; |
| import static com.google.common.collect.Iterables.limit; |
| |
| import com.google.caliper.BeforeExperiment; |
| import com.google.caliper.Benchmark; |
| import com.google.caliper.Param; |
| import com.google.caliper.api.Footprint; |
| import com.google.caliper.api.VmOptions; |
| import com.google.common.base.Supplier; |
| import com.google.common.collect.ImmutableList; |
| import com.google.common.primitives.Ints; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Random; |
| import java.util.concurrent.locks.Lock; |
| import java.util.concurrent.locks.ReentrantLock; |
| |
| /** A benchmark comparing the various striped implementations. */ |
| @VmOptions({"-Xms12g", "-Xmx12g", "-d64"}) |
| public class StripedBenchmark { |
| private static final Supplier<Lock> LOCK_SUPPLIER = |
| new Supplier<Lock>() { |
| @Override |
| public Lock get() { |
| return new ReentrantLock(); |
| } |
| }; |
| |
| @Param({"2", "8", "64", "1024", "65536"}) |
| int numStripes; |
| |
| @Param Impl impl; |
| |
| enum Impl { |
| EAGER { |
| @Override |
| Striped<Lock> get(int stripes) { |
| return Striped.lock(stripes); |
| } |
| }, |
| LAZY_SMALL { |
| @Override |
| Striped<Lock> get(int stripes) { |
| return new Striped.SmallLazyStriped<>(stripes, LOCK_SUPPLIER); |
| } |
| }, |
| LAZY_LARGE { |
| @Override |
| Striped<Lock> get(int stripes) { |
| return new Striped.LargeLazyStriped<>(stripes, LOCK_SUPPLIER); |
| } |
| }; |
| |
| abstract Striped<Lock> get(int stripes); |
| } |
| |
| private Striped<Lock> striped; |
| private int[] stripes; |
| private List<Integer> bulkGetSet; |
| |
| @BeforeExperiment |
| void setUp() { |
| this.striped = impl.get(numStripes); |
| stripes = new int[numStripes]; |
| for (int i = 0; i < numStripes; i++) { |
| stripes[i] = i; |
| } |
| List<Integer> asList = Ints.asList(stripes); |
| Collections.shuffle(asList, new Random(0xdeadbeef)); |
| |
| // do bulk gets with exactly 10 keys (possibly <10 stripes) (or less if numStripes is smaller) |
| bulkGetSet = ImmutableList.copyOf(limit(cycle(asList), 10)); |
| } |
| |
| @Footprint |
| Object sizeOfStriped() { |
| return impl.get(numStripes); |
| } |
| |
| // a place to put the locks in sizeOfPopulatedStriped so they don't get GC'd before we measure |
| final List<Lock> locks = new ArrayList<>(numStripes); |
| |
| @Footprint |
| Object sizeOfPopulatedStriped() { |
| locks.clear(); |
| Striped<Lock> striped = impl.get(numStripes); |
| for (int i : stripes) { |
| locks.add(striped.getAt(i)); |
| } |
| return striped; |
| } |
| |
| @Benchmark |
| long timeConstruct(long reps) { |
| long rvalue = 0; |
| int numStripesLocal = numStripes; |
| Impl implLocal = impl; |
| for (long i = 0; i < reps; i++) { |
| rvalue += implLocal.get(numStripesLocal).hashCode(); |
| } |
| return rvalue; |
| } |
| |
| @Benchmark |
| long timeGetAt(long reps) { |
| long rvalue = 0; |
| int[] stripesLocal = stripes; |
| int mask = numStripes - 1; |
| Striped<Lock> stripedLocal = striped; |
| for (long i = 0; i < reps; i++) { |
| rvalue += stripedLocal.getAt(stripesLocal[(int) (i & mask)]).hashCode(); |
| } |
| return rvalue; |
| } |
| |
| @Benchmark |
| long timeBulkGet(long reps) { |
| long rvalue = 0; |
| List<Integer> bulkGetSetLocal = bulkGetSet; |
| Striped<Lock> stripedLocal = striped; |
| for (long i = 0; i < reps; i++) { |
| rvalue += stripedLocal.bulkGet(bulkGetSetLocal).hashCode(); |
| } |
| return rvalue; |
| } |
| } |