Java tutorial
package org.apache.cassandra.utils; /* * * 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. * */ import java.lang.management.ManagementFactory; import java.util.Set; import javax.management.JMX; import javax.management.MBeanServer; import javax.management.MalformedObjectNameException; import javax.management.ObjectName; import com.google.common.collect.Iterables; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.apache.cassandra.concurrent.IExecutorMBean; import org.apache.cassandra.db.ColumnFamilyStore; import org.apache.cassandra.db.CompactionManager; import org.apache.cassandra.net.MessagingService; public class StatusLogger { private static final Logger logger = LoggerFactory.getLogger(StatusLogger.class); public static void log() { MBeanServer server = ManagementFactory.getPlatformMBeanServer(); // everything from o.a.c.concurrent logger.info(String.format("%-25s%10s%10s", "Pool Name", "Active", "Pending")); Set<ObjectName> request, internal; try { request = server.queryNames(new ObjectName("org.apache.cassandra.request:type=*"), null); internal = server.queryNames(new ObjectName("org.apache.cassandra.internal:type=*"), null); } catch (MalformedObjectNameException e) { throw new RuntimeException(e); } for (ObjectName objectName : Iterables.concat(request, internal)) { String poolName = objectName.getKeyProperty("type"); IExecutorMBean threadPoolProxy = JMX.newMBeanProxy(server, objectName, IExecutorMBean.class); logger.info(String.format("%-25s%10s%10s", poolName, threadPoolProxy.getActiveCount(), threadPoolProxy.getPendingTasks())); } // one offs logger.info(String.format("%-25s%10s%10s", "CompactionManager", "n/a", CompactionManager.instance.getPendingTasks())); int pendingCommands = 0; for (int n : MessagingService.instance().getCommandPendingTasks().values()) { pendingCommands += n; } int pendingResponses = 0; for (int n : MessagingService.instance().getResponsePendingTasks().values()) { pendingResponses += n; } logger.info(String.format("%-25s%10s%10s", "MessagingService", "n/a", pendingCommands + "," + pendingResponses)); // per-CF stats logger.info(String.format("%-25s%20s%20s%20s", "ColumnFamily", "Memtable ops,data", "Row cache size/cap", "Key cache size/cap")); for (ColumnFamilyStore cfs : ColumnFamilyStore.all()) { logger.info(String.format("%-25s%20s%20s%20s", cfs.table.name + "." + cfs.columnFamily, cfs.getMemtableColumnsCount() + "," + cfs.getMemtableDataSize(), cfs.getRowCacheSize() + "/" + cfs.getRowCacheCapacity(), cfs.getKeyCacheSize() + "/" + cfs.getKeyCacheCapacity())); } } }