| /** |
| * 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.hbase.ipc; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.hbase.DaemonThreadFactory; |
| |
| import java.io.IOException; |
| import java.util.concurrent.ArrayBlockingQueue; |
| import java.util.concurrent.ThreadPoolExecutor; |
| import java.util.concurrent.TimeUnit; |
| import java.util.concurrent.atomic.AtomicInteger; |
| |
| /** |
| * A very simple {@code }RpcScheduler} that serves incoming requests in order. |
| * |
| * This can be used for HMaster, where no prioritization is needed. |
| */ |
| public class FifoRpcScheduler extends RpcScheduler { |
| private static final Log LOG = LogFactory.getLog(FifoRpcScheduler.class); |
| private final int handlerCount; |
| private final int maxQueueLength; |
| private final AtomicInteger queueSize = new AtomicInteger(0); |
| private ThreadPoolExecutor executor; |
| |
| public FifoRpcScheduler(Configuration conf, int handlerCount) { |
| this.handlerCount = handlerCount; |
| this.maxQueueLength = conf.getInt(RpcScheduler.IPC_SERVER_MAX_CALLQUEUE_LENGTH, |
| handlerCount * RpcServer.DEFAULT_MAX_CALLQUEUE_LENGTH_PER_HANDLER); |
| LOG.info("Using " + this.getClass().getSimpleName() + " as user call queue; handlerCount=" + |
| handlerCount + "; maxQueueLength=" + maxQueueLength); |
| } |
| |
| @Override |
| public void init(Context context) { |
| // no-op |
| } |
| |
| @Override |
| public void start() { |
| this.executor = new ThreadPoolExecutor( |
| handlerCount, |
| handlerCount, |
| 60, |
| TimeUnit.SECONDS, |
| new ArrayBlockingQueue<Runnable>(maxQueueLength), |
| new DaemonThreadFactory("FifoRpcScheduler.handler"), |
| new ThreadPoolExecutor.CallerRunsPolicy()); |
| } |
| |
| @Override |
| public void stop() { |
| this.executor.shutdown(); |
| } |
| |
| @Override |
| public boolean dispatch(final CallRunner task) throws IOException, InterruptedException { |
| // Executors provide no offer, so make our own. |
| int queued = queueSize.getAndIncrement(); |
| if (maxQueueLength > 0 && queued >= maxQueueLength) { |
| queueSize.decrementAndGet(); |
| return false; |
| } |
| executor.submit(new Runnable() { |
| @Override |
| public void run() { |
| task.setStatus(RpcServer.getStatus()); |
| task.run(); |
| queueSize.decrementAndGet(); |
| } |
| }); |
| return true; |
| } |
| |
| @Override |
| public int getGeneralQueueLength() { |
| return executor.getQueue().size(); |
| } |
| |
| @Override |
| public int getPriorityQueueLength() { |
| return 0; |
| } |
| |
| @Override |
| public int getReplicationQueueLength() { |
| return 0; |
| } |
| |
| @Override |
| public int getActiveRpcHandlerCount() { |
| return executor.getActiveCount(); |
| } |
| |
| @Override |
| public long getNumGeneralCallsDropped() { |
| return 0; |
| } |
| |
| @Override |
| public long getNumLifoModeSwitches() { |
| return 0; |
| } |
| } |