| /** |
| * 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.hadoop.hdfs.server.datanode.metrics; |
| import java.util.Random; |
| |
| import javax.management.ObjectName; |
| import org.apache.hadoop.metrics.util.MBeanUtil; |
| import org.apache.hadoop.metrics.util.MetricsDynamicMBeanBase; |
| import org.apache.hadoop.metrics.util.MetricsRegistry; |
| |
| /** |
| * |
| * This is the JMX MBean for reporting the DataNode Activity. |
| * The MBean is register using the name |
| * "hadoop:service=DataNode,name=DataNodeActivity-<hostname>-<portNumber>" |
| * |
| * Many of the activity metrics are sampled and averaged on an interval |
| * which can be specified in the metrics config file. |
| * <p> |
| * For the metrics that are sampled and averaged, one must specify |
| * a metrics context that does periodic update calls. Most metrics contexts do. |
| * The default Null metrics context however does NOT. So if you aren't |
| * using any other metrics context then you can turn on the viewing and averaging |
| * of sampled metrics by specifying the following two lines |
| * in the hadoop-meterics.properties file: |
| * <pre> |
| * dfs.class=org.apache.hadoop.metrics.spi.NullContextWithUpdateThread |
| * dfs.period=10 |
| * </pre> |
| *<p> |
| * Note that the metrics are collected regardless of the context used. |
| * The context with the update thread is used to average the data periodically |
| * |
| * |
| * |
| * Impl details: We use a dynamic mbean that gets the list of the metrics |
| * from the metrics registry passed as an argument to the constructor |
| */ |
| |
| public class DataNodeActivityMBean extends MetricsDynamicMBeanBase { |
| final private ObjectName mbeanName; |
| private Random rand = new Random(); |
| |
| public DataNodeActivityMBean(final MetricsRegistry mr, |
| final String datanodeName) { |
| super(mr, "Activity statistics at the DataNode"); |
| String name; |
| if (datanodeName.equals("")) {// Temp fix for the uninitialized name |
| name = "UndefinedDataNodeName" + rand.nextInt(); |
| } else { |
| name = datanodeName.replace(":", "-"); |
| } |
| mbeanName = MBeanUtil.registerMBean("DataNode", |
| "DataNodeActivity-" + name, this); |
| } |
| |
| |
| public void shutdown() { |
| if (mbeanName != null) |
| MBeanUtil.unregisterMBean(mbeanName); |
| } |
| } |