001/*
002 * (C) Copyright 2017 Nuxeo (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 */
017package org.nuxeo.ecm.core.cache;
018
019import java.io.Serializable;
020
021import org.nuxeo.runtime.metrics.MetricsService;
022
023import com.codahale.metrics.Counter;
024import com.codahale.metrics.Gauge;
025import com.codahale.metrics.MetricRegistry;
026import com.codahale.metrics.RatioGauge;
027import com.codahale.metrics.SharedMetricRegistries;
028
029public class CacheMetrics extends CacheWrapper {
030
031    protected MetricRegistry registry;
032
033    protected Counter read;
034
035    protected Counter read_hit;
036
037    protected Counter read_miss;
038
039    protected RatioGauge read_hit_ratio;
040
041    protected Counter write;
042
043    protected Counter invalidation;
044
045    protected Gauge<Long> size;
046
047    protected final String READ_HIT_NAME = nameOf("read-hit-counter");
048
049    protected final String READ_HIT_RATIO_NAME = nameOf("read-hit-ratio");
050
051    protected final String READ_MISS_NAME = nameOf("read-miss-counter");
052
053    protected final String READ_NAME = nameOf("read-counter");
054
055    protected final String WRITE_NAME = nameOf("write-counter");
056
057    protected final String INVALIDATE_ALL_NAME = nameOf("invalidate-all-counter");
058
059    protected final String SIZE_NAME = nameOf("size");
060
061    protected String nameOf(String name) {
062        return MetricRegistry.name("nuxeo", "cache", getName(), name);
063    }
064
065    public CacheMetrics(CacheManagement cache) {
066        super(cache);
067    }
068
069    @Override
070    public void start() {
071        registry = SharedMetricRegistries.getOrCreate(MetricsService.class.getName());
072        read = registry.counter(READ_NAME);
073        read_hit = registry.counter(READ_HIT_NAME);
074        read_miss = registry.counter(READ_MISS_NAME);
075        registry.register(READ_HIT_RATIO_NAME, read_hit_ratio = new RatioGauge() {
076
077            @Override
078            protected Ratio getRatio() {
079                Ratio ratio = Ratio.of(read_hit.getCount(), read.getCount());
080                return ratio;
081            }
082        });
083        write = registry.counter(WRITE_NAME);
084        invalidation = registry.counter(INVALIDATE_ALL_NAME);
085        registry.register(SIZE_NAME, size = new Gauge<Long>() {
086
087            @Override
088            public Long getValue() {
089                return Long.valueOf(getSize());
090            }
091        });
092    }
093
094    @Override
095    public void stop() {
096        registry.remove(READ_NAME);
097        registry.remove(READ_HIT_NAME);
098        registry.remove(READ_MISS_NAME);
099        registry.remove(READ_HIT_RATIO_NAME);
100        registry.remove(WRITE_NAME);
101        registry.remove(INVALIDATE_ALL_NAME);
102        registry.remove(SIZE_NAME);
103    }
104
105    @Override
106    public Serializable get(String key) {
107        Serializable value = super.get(key);
108        read.inc();
109        if (value != null || super.hasEntry(key)) {
110            read_hit.inc();
111        } else {
112            read_miss.inc();
113        }
114        return value;
115    }
116
117    @Override
118    public void put(String key, Serializable value) {
119        try {
120            super.put(key, value);
121        } finally {
122            write.inc();
123        }
124    }
125
126    @Override
127    public void invalidateAll() {
128        try {
129            super.invalidateAll();
130        } finally {
131            invalidation.inc();
132        }
133    }
134
135}