/*
* Copyright 2015 Gilga Einziger. All Rights Reserved.
*
* 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.github.benmanes.caffeine.cache.simulator.policy.sketch.tinycache;
import java.util.Set;
import com.github.benmanes.caffeine.cache.simulator.BasicSettings;
import com.github.benmanes.caffeine.cache.simulator.admission.tinycache.TinyCacheWithGhostCache;
import com.github.benmanes.caffeine.cache.simulator.policy.Policy;
import com.github.benmanes.caffeine.cache.simulator.policy.PolicyStats;
import com.google.common.collect.ImmutableSet;
import com.typesafe.config.Config;
/**
* @author gilga1983@gmail.com (Gil Einziger)
*/
public final class TinyCacheWithGhostCachePolicy implements Policy {
private final TinyCacheWithGhostCache tinyCache;
private final PolicyStats policyStats;
public TinyCacheWithGhostCachePolicy(Config config) {
BasicSettings settings = new BasicSettings(config);
this.policyStats = new PolicyStats("sketch.TinyCache_GhostCache");
tinyCache = new TinyCacheWithGhostCache((int) Math.ceil(settings.maximumSize() / 64.0),
64, settings.randomSeed());
}
/** Returns all variations of this policy based on the configuration parameters. */
public static Set<Policy> policies(Config config) {
return ImmutableSet.of(new TinyCacheWithGhostCachePolicy(config));
}
@Override
public void record(long key) {
if (tinyCache.contains(key)) {
tinyCache.recordItem(key);
policyStats.recordHit();
} else {
boolean evicted = tinyCache.addItem(key);
tinyCache.recordItem(key);
policyStats.recordMiss();
if (evicted) {
policyStats.recordEviction();
}
}
}
@Override
public PolicyStats stats() {
return policyStats;
}
}