17dd252788645e940eada959bdde927426e2531c9Paul Duffin/* 27dd252788645e940eada959bdde927426e2531c9Paul Duffin * Copyright (C) 2010 The Guava Authors 37dd252788645e940eada959bdde927426e2531c9Paul Duffin * 47dd252788645e940eada959bdde927426e2531c9Paul Duffin * Licensed under the Apache License, Version 2.0 (the "License"); 57dd252788645e940eada959bdde927426e2531c9Paul Duffin * you may not use this file except in compliance with the License. 67dd252788645e940eada959bdde927426e2531c9Paul Duffin * You may obtain a copy of the License at 77dd252788645e940eada959bdde927426e2531c9Paul Duffin * 87dd252788645e940eada959bdde927426e2531c9Paul Duffin * http://www.apache.org/licenses/LICENSE-2.0 97dd252788645e940eada959bdde927426e2531c9Paul Duffin * 107dd252788645e940eada959bdde927426e2531c9Paul Duffin * Unless required by applicable law or agreed to in writing, software 117dd252788645e940eada959bdde927426e2531c9Paul Duffin * distributed under the License is distributed on an "AS IS" BASIS, 127dd252788645e940eada959bdde927426e2531c9Paul Duffin * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 137dd252788645e940eada959bdde927426e2531c9Paul Duffin * See the License for the specific language governing permissions and 147dd252788645e940eada959bdde927426e2531c9Paul Duffin * limitations under the License. 157dd252788645e940eada959bdde927426e2531c9Paul Duffin */ 167dd252788645e940eada959bdde927426e2531c9Paul Duffin 177dd252788645e940eada959bdde927426e2531c9Paul Duffinpackage com.google.common.cache; 187dd252788645e940eada959bdde927426e2531c9Paul Duffin 190888a09821a98ac0680fad765217302858e70fa4Paul Duffinimport com.google.caliper.AfterExperiment; 200888a09821a98ac0680fad765217302858e70fa4Paul Duffinimport com.google.caliper.BeforeExperiment; 210888a09821a98ac0680fad765217302858e70fa4Paul Duffinimport com.google.caliper.Benchmark; 227dd252788645e940eada959bdde927426e2531c9Paul Duffinimport com.google.caliper.Param; 237dd252788645e940eada959bdde927426e2531c9Paul Duffinimport com.google.common.primitives.Ints; 247dd252788645e940eada959bdde927426e2531c9Paul Duffin 257dd252788645e940eada959bdde927426e2531c9Paul Duffinimport java.util.Random; 267dd252788645e940eada959bdde927426e2531c9Paul Duffinimport java.util.concurrent.atomic.AtomicLong; 277dd252788645e940eada959bdde927426e2531c9Paul Duffin 287dd252788645e940eada959bdde927426e2531c9Paul Duffin/** 297dd252788645e940eada959bdde927426e2531c9Paul Duffin * Single-threaded benchmark for {@link LoadingCache}. 307dd252788645e940eada959bdde927426e2531c9Paul Duffin * 317dd252788645e940eada959bdde927426e2531c9Paul Duffin * @author Charles Fry 327dd252788645e940eada959bdde927426e2531c9Paul Duffin */ 330888a09821a98ac0680fad765217302858e70fa4Paul Duffinpublic class LoadingCacheSingleThreadBenchmark { 347dd252788645e940eada959bdde927426e2531c9Paul Duffin @Param({"1000", "2000"}) int maximumSize; 357dd252788645e940eada959bdde927426e2531c9Paul Duffin @Param("5000") int distinctKeys; 367dd252788645e940eada959bdde927426e2531c9Paul Duffin @Param("4") int segments; 377dd252788645e940eada959bdde927426e2531c9Paul Duffin 387dd252788645e940eada959bdde927426e2531c9Paul Duffin // 1 means uniform likelihood of keys; higher means some keys are more popular 397dd252788645e940eada959bdde927426e2531c9Paul Duffin // tweak this to control hit rate 407dd252788645e940eada959bdde927426e2531c9Paul Duffin @Param("2.5") double concentration; 417dd252788645e940eada959bdde927426e2531c9Paul Duffin 427dd252788645e940eada959bdde927426e2531c9Paul Duffin Random random = new Random(); 437dd252788645e940eada959bdde927426e2531c9Paul Duffin 447dd252788645e940eada959bdde927426e2531c9Paul Duffin LoadingCache<Integer, Integer> cache; 457dd252788645e940eada959bdde927426e2531c9Paul Duffin 467dd252788645e940eada959bdde927426e2531c9Paul Duffin int max; 477dd252788645e940eada959bdde927426e2531c9Paul Duffin 487dd252788645e940eada959bdde927426e2531c9Paul Duffin static AtomicLong requests = new AtomicLong(0); 497dd252788645e940eada959bdde927426e2531c9Paul Duffin static AtomicLong misses = new AtomicLong(0); 507dd252788645e940eada959bdde927426e2531c9Paul Duffin 510888a09821a98ac0680fad765217302858e70fa4Paul Duffin @BeforeExperiment void setUp() { 527dd252788645e940eada959bdde927426e2531c9Paul Duffin // random integers will be generated in this range, then raised to the 537dd252788645e940eada959bdde927426e2531c9Paul Duffin // power of (1/concentration) and floor()ed 547dd252788645e940eada959bdde927426e2531c9Paul Duffin max = Ints.checkedCast((long) Math.pow(distinctKeys, concentration)); 557dd252788645e940eada959bdde927426e2531c9Paul Duffin 567dd252788645e940eada959bdde927426e2531c9Paul Duffin cache = CacheBuilder.newBuilder() 577dd252788645e940eada959bdde927426e2531c9Paul Duffin .concurrencyLevel(segments) 587dd252788645e940eada959bdde927426e2531c9Paul Duffin .maximumSize(maximumSize) 597dd252788645e940eada959bdde927426e2531c9Paul Duffin .build( 607dd252788645e940eada959bdde927426e2531c9Paul Duffin new CacheLoader<Integer, Integer>() { 617dd252788645e940eada959bdde927426e2531c9Paul Duffin @Override public Integer load(Integer from) { 627dd252788645e940eada959bdde927426e2531c9Paul Duffin return (int) misses.incrementAndGet(); 637dd252788645e940eada959bdde927426e2531c9Paul Duffin } 647dd252788645e940eada959bdde927426e2531c9Paul Duffin }); 657dd252788645e940eada959bdde927426e2531c9Paul Duffin 667dd252788645e940eada959bdde927426e2531c9Paul Duffin // To start, fill up the cache. 677dd252788645e940eada959bdde927426e2531c9Paul Duffin // Each miss both increments the counter and causes the map to grow by one, 687dd252788645e940eada959bdde927426e2531c9Paul Duffin // so until evictions begin, the size of the map is the greatest return 697dd252788645e940eada959bdde927426e2531c9Paul Duffin // value seen so far 707dd252788645e940eada959bdde927426e2531c9Paul Duffin while (cache.getUnchecked(nextRandomKey()) < maximumSize) {} 717dd252788645e940eada959bdde927426e2531c9Paul Duffin 727dd252788645e940eada959bdde927426e2531c9Paul Duffin requests.set(0); 737dd252788645e940eada959bdde927426e2531c9Paul Duffin misses.set(0); 747dd252788645e940eada959bdde927426e2531c9Paul Duffin } 757dd252788645e940eada959bdde927426e2531c9Paul Duffin 760888a09821a98ac0680fad765217302858e70fa4Paul Duffin @Benchmark int time(int reps) { 777dd252788645e940eada959bdde927426e2531c9Paul Duffin int dummy = 0; 787dd252788645e940eada959bdde927426e2531c9Paul Duffin for (int i = 0; i < reps; i++) { 797dd252788645e940eada959bdde927426e2531c9Paul Duffin dummy += cache.getUnchecked(nextRandomKey()); 807dd252788645e940eada959bdde927426e2531c9Paul Duffin } 817dd252788645e940eada959bdde927426e2531c9Paul Duffin requests.addAndGet(reps); 827dd252788645e940eada959bdde927426e2531c9Paul Duffin return dummy; 837dd252788645e940eada959bdde927426e2531c9Paul Duffin } 847dd252788645e940eada959bdde927426e2531c9Paul Duffin 857dd252788645e940eada959bdde927426e2531c9Paul Duffin private int nextRandomKey() { 867dd252788645e940eada959bdde927426e2531c9Paul Duffin int a = random.nextInt(max); 877dd252788645e940eada959bdde927426e2531c9Paul Duffin 887dd252788645e940eada959bdde927426e2531c9Paul Duffin /* 897dd252788645e940eada959bdde927426e2531c9Paul Duffin * For example, if concentration=2.0, the following takes the square root of 907dd252788645e940eada959bdde927426e2531c9Paul Duffin * the uniformly-distributed random integer, then truncates any fractional 917dd252788645e940eada959bdde927426e2531c9Paul Duffin * part, so higher integers would appear (in this case linearly) more often 927dd252788645e940eada959bdde927426e2531c9Paul Duffin * than lower ones. 937dd252788645e940eada959bdde927426e2531c9Paul Duffin */ 947dd252788645e940eada959bdde927426e2531c9Paul Duffin return (int) Math.pow(a, 1.0 / concentration); 957dd252788645e940eada959bdde927426e2531c9Paul Duffin } 967dd252788645e940eada959bdde927426e2531c9Paul Duffin 970888a09821a98ac0680fad765217302858e70fa4Paul Duffin @AfterExperiment void tearDown() { 987dd252788645e940eada959bdde927426e2531c9Paul Duffin double req = requests.get(); 997dd252788645e940eada959bdde927426e2531c9Paul Duffin double hit = req - misses.get(); 1007dd252788645e940eada959bdde927426e2531c9Paul Duffin 1017dd252788645e940eada959bdde927426e2531c9Paul Duffin // Currently, this is going into /dev/null, but I'll fix that 1027dd252788645e940eada959bdde927426e2531c9Paul Duffin System.out.println("hit rate: " + hit / req); 1037dd252788645e940eada959bdde927426e2531c9Paul Duffin } 1047dd252788645e940eada959bdde927426e2531c9Paul Duffin 1057dd252788645e940eada959bdde927426e2531c9Paul Duffin // for proper distributions later: 1067dd252788645e940eada959bdde927426e2531c9Paul Duffin // import JSci.maths.statistics.ProbabilityDistribution; 1077dd252788645e940eada959bdde927426e2531c9Paul Duffin // int key = (int) dist.inverse(random.nextDouble()); 1087dd252788645e940eada959bdde927426e2531c9Paul Duffin} 109