/*
* Copyright (C) 2010 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.collect;
import static com.google.common.collect.Lists.newArrayList;
import com.google.caliper.BeforeExperiment;
import com.google.caliper.Benchmark;
import com.google.caliper.Param;
import com.google.common.collect.CollectionBenchmarkSampleData.Element;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentSkipListMap;
/**
* A microbenchmark that tests the performance of get() and iteration on various map
* implementations. Forked from {@link SetContainsBenchmark}.
*
* @author Nicholaus Shupe
*/
public class MapBenchmark {
@Param({"Hash", "LinkedHM", "MapMaker1", "Immutable"})
private Impl impl;
public enum Impl {
Hash {
@Override Map<Element, Element> create(Collection<Element> keys) {
Map<Element, Element> map = Maps.newHashMap();
for (Element element: keys) {
map.put(element, element);
}
return map;
}
},
LinkedHM {
@Override Map<Element, Element> create(Collection<Element> keys) {
Map<Element, Element> map = Maps.newLinkedHashMap();
for (Element element: keys) {
map.put(element, element);
}
return map;
}
},
UnmodHM {
@Override Map<Element, Element> create(Collection<Element> keys) {
return Collections.unmodifiableMap(Hash.create(keys));
}
},
SyncHM {
@Override Map<Element, Element> create(Collection<Element> keys) {
return Collections.synchronizedMap(Hash.create(keys));
}
},
Tree {
@Override Map<Element, Element> create(Collection<Element> keys) {
Map<Element, Element> map = Maps.newTreeMap();
for (Element element: keys) {
map.put(element, element);
}
return map;
}
},
SkipList {
@Override Map<Element, Element> create(Collection<Element> keys) {
Map<Element, Element> map = new ConcurrentSkipListMap<Element, Element>();
for (Element element: keys) {
map.put(element, element);
}
return map;
}
},
ConcurrentHM1 {
@Override Map<Element, Element> create(Collection<Element> keys) {
Map<Element, Element> map =
new ConcurrentHashMap<Element, Element>(keys.size(), 0.75f, 1);
for (Element element: keys) {
map.put(element, element);
}
return map;
}
},
ConcurrentHM16 {
@Override Map<Element, Element> create(Collection<Element> keys) {
Map<Element, Element> map =
new ConcurrentHashMap<Element, Element>(keys.size(), 0.75f, 16);
for (Element element: keys) {
map.put(element, element);
}
return map;
}
},
MapMaker1 {
@Override Map<Element, Element> create(Collection<Element> keys) {
Map<Element, Element> map = new MapMaker()
.concurrencyLevel(1)
.makeMap();
for (Element element: keys) {
map.put(element, element);
}
return map;
}
},
MapMaker16 {
@Override Map<Element, Element> create(Collection<Element> keys) {
Map<Element, Element> map = new MapMaker()
.concurrencyLevel(16)
.makeMap();
for (Element element: keys) {
map.put(element, element);
}
return map;
}
},
Immutable {
@Override Map<Element, Element> create(Collection<Element> keys) {
ImmutableMap.Builder<Element, Element> builder = ImmutableMap.builder();
for (Element element : keys) {
builder.put(element, element);
}
return builder.build();
}
},
ImmutableSorted {
@Override Map<Element, Element> create(Collection<Element> keys) {
ImmutableSortedMap.Builder<Element, Element> builder =
ImmutableSortedMap.naturalOrder();
for (Element element : keys) {
builder.put(element, element);
}
return builder.build();
}
};
abstract Map<Element, Element> create(Collection<Element> contents);
}
@Param({"5", "50", "500", "5000", "50000"})
private int size;
// TODO: look at exact (==) hits vs. equals() hits?
@Param("0.9")
private double hitRate;
@Param("true")
private boolean isUserTypeFast;
// "" means no fixed seed
@Param("")
private SpecialRandom random;
@Param("false")
private boolean sortedData;
// the following must be set during setUp
private Element[] queries;
private Map<Element, Element> mapToTest;
private Collection<Element> values;
@BeforeExperiment void setUp() {
CollectionBenchmarkSampleData sampleData =
new CollectionBenchmarkSampleData(
isUserTypeFast, random, hitRate, size);
if (sortedData) {
List<Element> valueList = newArrayList(sampleData.getValuesInSet());
Collections.sort(valueList);
values = valueList;
} else {
values = sampleData.getValuesInSet();
}
this.mapToTest = impl.create(values);
this.queries = sampleData.getQueries();
}
@Benchmark boolean get(int reps) {
// Paranoia: acting on hearsay that accessing fields might be slow
// Should write a benchmark to test that!
Map<Element, Element> map = mapToTest;
Element[] queries = this.queries;
// Allows us to use & instead of %, acting on hearsay that division
// operators (/%) are disproportionately expensive; should test this too!
int mask = queries.length - 1;
boolean dummy = false;
for (int i = 0; i < reps; i++) {
dummy ^= map.get(queries[i & mask]) != null;
}
return dummy;
}
@Benchmark int createAndPopulate(int reps) {
int dummy = 0;
for (int i = 0; i < reps; i++) {
dummy += impl.create(values).size();
}
return dummy;
}
@Benchmark boolean iterateWithEntrySet(int reps) {
Map<Element, Element> map = mapToTest;
boolean dummy = false;
for (int i = 0; i < reps; i++) {
for (Map.Entry<Element, Element> entry : map.entrySet()) {
dummy ^= entry.getKey() != entry.getValue();
}
}
return dummy;
}
@Benchmark boolean iterateWithKeySetAndGet(int reps) {
Map<Element, Element> map = mapToTest;
boolean dummy = false;
for (int i = 0; i < reps; i++) {
for (Element key : map.keySet()) {
Element value = map.get(key);
dummy ^= key != value;
}
}
return dummy;
}
}