• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2011 The Guava Authors
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.common.cache;
18 
19 import com.google.caliper.BeforeExperiment;
20 import com.google.caliper.Benchmark;
21 import com.google.caliper.Param;
22 import com.google.common.cache.LocalCache.ReferenceEntry;
23 import com.google.common.cache.LocalCache.Segment;
24 
25 /**
26  * Benchmark for {@code LocalCache.Segment.removeEntryFromChain}.
27  *
28  * @author Charles Fry
29  */
30 public class ChainBenchmark {
31 
32   @Param({"1", "2", "3", "4", "5", "6"}) int length;
33 
34   private Segment<Object, Object> segment;
35   private ReferenceEntry<Object, Object> head;
36   private ReferenceEntry<Object, Object> chain;
37 
38   @BeforeExperiment
setUp()39   void setUp() {
40     LocalCache<Object, Object> cache = new LocalCache<Object, Object>(
41         CacheBuilder.newBuilder()
42             .concurrencyLevel(1), null);
43     segment = cache.segments[0];
44     chain = null;
45     for (int i = 0; i < length; i++) {
46       Object key = new Object();
47       chain = segment.newEntry(key, cache.hash(key), chain);
48       if (i == 0) {
49         head = chain;
50       }
51     }
52   }
53 
time(int reps)54   @Benchmark int time(int reps) {
55     int dummy = 0;
56     for (int i = 0; i < reps; i++) {
57       segment.removeEntryFromChain(chain, head);
58       dummy += segment.count;
59     }
60     return dummy;
61   }
62 }
63