001/** 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018 019package org.apache.hadoop.lib.service.scheduler; 020 021import org.apache.hadoop.classification.InterfaceAudience; 022import org.apache.hadoop.lib.lang.RunnableCallable; 023import org.apache.hadoop.lib.server.BaseService; 024import org.apache.hadoop.lib.server.Server; 025import org.apache.hadoop.lib.server.ServiceException; 026import org.apache.hadoop.lib.service.Instrumentation; 027import org.apache.hadoop.lib.service.Scheduler; 028import org.apache.hadoop.lib.util.Check; 029import org.apache.hadoop.util.Time; 030import org.slf4j.Logger; 031import org.slf4j.LoggerFactory; 032 033import java.text.MessageFormat; 034import java.util.concurrent.Callable; 035import java.util.concurrent.ScheduledExecutorService; 036import java.util.concurrent.ScheduledThreadPoolExecutor; 037import java.util.concurrent.TimeUnit; 038 039@InterfaceAudience.Private 040public class SchedulerService extends BaseService implements Scheduler { 041 private static final Logger LOG = LoggerFactory.getLogger(SchedulerService.class); 042 043 private static final String INST_GROUP = "scheduler"; 044 045 public static final String PREFIX = "scheduler"; 046 047 public static final String CONF_THREADS = "threads"; 048 049 private ScheduledExecutorService scheduler; 050 051 public SchedulerService() { 052 super(PREFIX); 053 } 054 055 @Override 056 public void init() throws ServiceException { 057 int threads = getServiceConfig().getInt(CONF_THREADS, 5); 058 scheduler = new ScheduledThreadPoolExecutor(threads); 059 LOG.debug("Scheduler started"); 060 } 061 062 @Override 063 public void destroy() { 064 try { 065 long limit = Time.now() + 30 * 1000; 066 scheduler.shutdownNow(); 067 while (!scheduler.awaitTermination(1000, TimeUnit.MILLISECONDS)) { 068 LOG.debug("Waiting for scheduler to shutdown"); 069 if (Time.now() > limit) { 070 LOG.warn("Gave up waiting for scheduler to shutdown"); 071 break; 072 } 073 } 074 if (scheduler.isTerminated()) { 075 LOG.debug("Scheduler shutdown"); 076 } 077 } catch (InterruptedException ex) { 078 LOG.warn(ex.getMessage(), ex); 079 } 080 } 081 082 @Override 083 public Class[] getServiceDependencies() { 084 return new Class[]{Instrumentation.class}; 085 } 086 087 @Override 088 public Class getInterface() { 089 return Scheduler.class; 090 } 091 092 @Override 093 public void schedule(final Callable<?> callable, long delay, long interval, TimeUnit unit) { 094 Check.notNull(callable, "callable"); 095 if (!scheduler.isShutdown()) { 096 LOG.debug("Scheduling callable [{}], interval [{}] seconds, delay [{}] in [{}]", 097 new Object[]{callable, delay, interval, unit}); 098 Runnable r = new Runnable() { 099 @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 129 public void schedule(Runnable runnable, long delay, long interval, TimeUnit unit) { 130 schedule((Callable<?>) new RunnableCallable(runnable), delay, interval, unit); 131 } 132 133}