hadoop作业调度-资料

淑昊柠

file:///C:/DOCUME%7E1/ADMINI%7E1/LOCALS%7E1/Temp/EverNoteTempDir/ContractedBlock.giffile:///C:/DOCUME%7E1/ADMINI%7E1/LOCALS%7E1/Temp/EverNoteTempDir/ExpandedBlockStart.gifCode　　public synchronized HeartbeatResponse heartbeat(TaskTrackerStatus status,
　　boolean restarted, boolean initialContact,
　　boolean acceptNewTasks, short responseId) throws IOException {

file:///C:/DOCUME%7E1/ADMINI%7E1/LOCALS%7E1/Temp/EverNoteTempDir/dot.gif

　　// 如果当次心跳允许指派任务，且当前上报心跳的taskTracker可接收新task(传入的acceptNewTasks为true)
　　//, 并且其不在黑名单中, 则进入调度
　　if (recoveryManager.shouldSchedule() && acceptNewTasks && !isBlacklisted) {
　　TaskTrackerStatus taskTrackerStatus = getTaskTracker(trackerName);
　　if (taskTrackerStatus == null) {
　　LOG.warn("Unknown task tracker polling; ignoring: " + trackerName);
　　} else {
　　List tasks = getSetupAndCleanupTasks(taskTrackerStatus);
　　if (tasks == null) {
　　// 调用具体的taskScheduler实现来为当前taskTracker指派任务
　　tasks = taskScheduler.assignTasks(taskTrackerStatus);
　　}
　　if (tasks != null) {
　　for (Task task : tasks) {
　　expireLaunchingTasks.addNewTask(task.getTaskID());
　　LOG.debug(trackerName + " -> LaunchTask: " + task.getTaskID());
　　actions.add(new LaunchTaskAction(task));
　　}
　　}
　　}
　　}
　　...
　　}