1 /** 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 package org.apache.hadoop.lib.service.scheduler; 20 21 import org.apache.hadoop.classification.InterfaceAudience; 22 import org.apache.hadoop.lib.lang.RunnableCallable; 23 import org.apache.hadoop.lib.server.BaseService; 24 import org.apache.hadoop.lib.server.Server; 25 import org.apache.hadoop.lib.server.ServiceException; 26 import org.apache.hadoop.lib.service.Instrumentation; 27 import org.apache.hadoop.lib.service.Scheduler; 28 import org.apache.hadoop.lib.util.Check; 29 import org.apache.hadoop.util.Time; 30 import org.slf4j.Logger; 31 import org.slf4j.LoggerFactory; 32 33 import java.text.MessageFormat; 34 import java.util.concurrent.Callable; 35 import java.util.concurrent.ScheduledExecutorService; 36 import java.util.concurrent.ScheduledThreadPoolExecutor; 37 import java.util.concurrent.TimeUnit; 38 39 @InterfaceAudience.Private 40 public class SchedulerService extends BaseService implements Scheduler { 41 private static final Logger LOG = LoggerFactory.getLogger(SchedulerService.class); 42 43 private static final String INST_GROUP = "scheduler"; 44 45 public static final String PREFIX = "scheduler"; 46 47 public static final String CONF_THREADS = "threads"; 48 49 private ScheduledExecutorService scheduler; 50 SchedulerService()51 public SchedulerService() { 52 super(PREFIX); 53 } 54 55 @Override init()56 public void init() throws ServiceException { 57 int threads = getServiceConfig().getInt(CONF_THREADS, 5); 58 scheduler = new ScheduledThreadPoolExecutor(threads); 59 LOG.debug("Scheduler started"); 60 } 61 62 @Override destroy()63 public void destroy() { 64 try { 65 long limit = Time.now() + 30 * 1000; 66 scheduler.shutdownNow(); 67 while (!scheduler.awaitTermination(1000, TimeUnit.MILLISECONDS)) { 68 LOG.debug("Waiting for scheduler to shutdown"); 69 if (Time.now() > limit) { 70 LOG.warn("Gave up waiting for scheduler to shutdown"); 71 break; 72 } 73 } 74 if (scheduler.isTerminated()) { 75 LOG.debug("Scheduler shutdown"); 76 } 77 } catch (InterruptedException ex) { 78 LOG.warn(ex.getMessage(), ex); 79 } 80 } 81 82 @Override getServiceDependencies()83 public Class[] getServiceDependencies() { 84 return new Class[]{Instrumentation.class}; 85 } 86 87 @Override getInterface()88 public Class getInterface() { 89 return Scheduler.class; 90 } 91 92 @Override schedule(final Callable<?> callable, long delay, long interval, TimeUnit unit)93 public void schedule(final Callable<?> callable, long delay, long interval, TimeUnit unit) { 94 Check.notNull(callable, "callable"); 95 if (!scheduler.isShutdown()) { 96 LOG.debug("Scheduling callable [{}], interval [{}] seconds, delay [{}] in [{}]", 97 new Object[]{callable, delay, interval, unit}); 98 Runnable r = new Runnable() { 99 @Override 100 public void run() { 101 String instrName = callable.getClass().getSimpleName(); 102 Instrumentation instr = getServer().get(Instrumentation.class); 103 if (getServer().getStatus() == Server.Status.HALTED) { 104 LOG.debug("Skipping [{}], server status [{}]", callable, getServer().getStatus()); 105 instr.incr(INST_GROUP, instrName + ".skips", 1); 106 } else { 107 LOG.debug("Executing [{}]", callable); 108 instr.incr(INST_GROUP, instrName + ".execs", 1); 109 Instrumentation.Cron cron = instr.createCron().start(); 110 try { 111 callable.call(); 112 } catch (Exception ex) { 113 instr.incr(INST_GROUP, instrName + ".fails", 1); 114 LOG.error("Error executing [{}], {}", new Object[]{callable, ex.getMessage(), ex}); 115 } finally { 116 instr.addCron(INST_GROUP, instrName, cron.stop()); 117 } 118 } 119 } 120 }; 121 scheduler.scheduleWithFixedDelay(r, delay, interval, unit); 122 } else { 123 throw new IllegalStateException( 124 MessageFormat.format("Scheduler shutting down, ignoring scheduling of [{}]", callable)); 125 } 126 } 127 128 @Override schedule(Runnable runnable, long delay, long interval, TimeUnit unit)129 public void schedule(Runnable runnable, long delay, long interval, TimeUnit unit) { 130 schedule((Callable<?>) new RunnableCallable(runnable), delay, interval, unit); 131 } 132 133 } 134