| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.cassandra.metrics; |
| |
| import java.util.concurrent.TimeUnit; |
| |
| import com.yammer.metrics.Metrics; |
| import com.yammer.metrics.core.Gauge; |
| import com.yammer.metrics.core.Meter; |
| import com.yammer.metrics.core.MetricName; |
| import com.yammer.metrics.util.RatioGauge; |
| import org.apache.cassandra.service.FileCacheService; |
| |
| public class FileCacheMetrics |
| { |
| private static final MetricNameFactory factory = new DefaultNameFactory("FileCache"); |
| |
| /** Total number of hits */ |
| public final Meter hits; |
| /** Total number of requests */ |
| public final Meter requests; |
| /** hit rate */ |
| public final Gauge<Double> hitRate; |
| /** Total size of file cache, in bytes */ |
| public final Gauge<Long> size; |
| |
| public FileCacheMetrics() |
| { |
| hits = Metrics.newMeter(factory.createMetricName("Hits"), "hits", TimeUnit.SECONDS); |
| requests = Metrics.newMeter(factory.createMetricName("Requests"), "requests", TimeUnit.SECONDS); |
| hitRate = Metrics.newGauge(factory.createMetricName("HitRate"), new RatioGauge() |
| { |
| protected double getNumerator() |
| { |
| return hits.count(); |
| } |
| |
| protected double getDenominator() |
| { |
| return requests.count(); |
| } |
| }); |
| size = Metrics.newGauge(factory.createMetricName("Size"), new Gauge<Long>() |
| { |
| public Long value() |
| { |
| return FileCacheService.instance.sizeInBytes(); |
| } |
| }); |
| } |
| } |