Java ClusterStatus.getMaxMapTasks方法代码示例

import org.apache.hadoop.mapred.ClusterStatus; //导入方法依赖的package包/类
/**
 * Generates an XML-formatted block that summarizes the state of the JobTracker.
 */
public void generateSummaryTable(JspWriter out,
                                 JobTracker tracker) throws IOException {
  ClusterStatus status = tracker.getClusterStatus();
  int maxMapTasks = status.getMaxMapTasks();
  int maxReduceTasks = status.getMaxReduceTasks();
  int numTaskTrackers = status.getTaskTrackers();
  String tasksPerNodeStr;
  if (numTaskTrackers > 0) {
    double tasksPerNodePct = (double) (maxMapTasks + maxReduceTasks) / (double) numTaskTrackers;
    tasksPerNodeStr = percentFormat.format(tasksPerNodePct);
  } else {
    tasksPerNodeStr = "-";
  }
  out.print("<maps>" + status.getMapTasks() + "</maps>\n" +
          "<reduces>" + status.getReduceTasks() + "</reduces>\n" +
          "<total_submissions>" + tracker.getTotalSubmissions() + "</total_submissions>\n" +
          "<nodes>" + status.getTaskTrackers() + "</nodes>\n" +
          "<map_task_capacity>" + status.getMaxMapTasks() + "</map_task_capacity>\n" +
          "<reduce_task_capacity>" + status.getMaxReduceTasks() + "</reduce_task_capacity>\n" +
          "<avg_tasks_per_node>" + tasksPerNodeStr + "</avg_tasks_per_node>\n");
}
 

import org.apache.hadoop.mapred.ClusterStatus; //导入方法依赖的package包/类
/**
 * Analyzes properties of hadoop cluster and configuration.
 */
private static void analyzeHadoopCluster() {
	try {
		JobConf job = ConfigurationManager.getCachedJobConf();
		JobClient client = new JobClient(job);
		ClusterStatus stat = client.getClusterStatus();
		if( stat != null ) { //if in cluster mode
			//analyze cluster status
			_remotePar = stat.getTaskTrackers();
			_remoteParMap = stat.getMaxMapTasks(); 
			_remoteParReduce = stat.getMaxReduceTasks(); 
			
			//analyze pure configuration properties
			analyzeHadoopConfiguration();
		}
	} 
	catch (IOException e) {
		throw new RuntimeException("Unable to analyze infrastructure.",e);
	}
}
 

import org.apache.hadoop.mapred.ClusterStatus; //导入方法依赖的package包/类
/**
 * Gets the number of input splits. First, tries the corresponding property,
 * then falls back to the number of available slots.
 *
 * @param context job context
 * @return number of input splits
 */
private int getSuggestedNumberOfSplits(JobContext context) throws IOException {
    int numberOfSplits;
    Configuration conf = context.getConfiguration();
    numberOfSplits = conf.getInt(inputNumberOfSplitsProperty, -1);
    if (numberOfSplits > 0) return numberOfSplits;
    if (HServerParameters.isHServerJob(context.getConfiguration())) { //We are running a hServer job, not a Hadoop job
        return HSERVER_JOB_DEFAULT_NUMBER_OF_SPLITS;
    }
    try {
        ClusterStatus status = (new JobClient((JobConf) context.getConfiguration())).getClusterStatus();
        numberOfSplits = status.getMaxMapTasks() - status.getMapTasks();
        if (numberOfSplits > 0) return numberOfSplits;
    } catch (Throwable t) {
        //Do nothing, will fall back to default;
    }
    return DEFAULT_NUMBER_OF_SPLITS;
}
 

import org.apache.hadoop.mapred.ClusterStatus; //导入方法依赖的package包/类
public static final int getNumAvailableMaps () throws IOException {
	JobConf job = new JobConf(Utils.class);
	JobClient client = new JobClient(job);
	ClusterStatus cluster = client.getClusterStatus();
	int maxMaps = cluster.getMaxMapTasks();
	int runnings = cluster.getMapTasks();
	return maxMaps - runnings;
}
 

import org.apache.hadoop.mapred.ClusterStatus; //导入方法依赖的package包/类
public int getNumSlotsForStore() throws IOException {
    ClusterStatus clusterStatus = getClusterStatus();
    // get the number of slots allocated to the store
    return isStoreInMapSide() ?
        clusterStatus.getMaxMapTasks() :
        clusterStatus.getMaxReduceTasks();
}
 

import org.apache.hadoop.mapred.ClusterStatus; //导入方法依赖的package包/类
public static final int getMaxNumMaps () throws IOException {
	JobConf job = new JobConf(Utils.class);
	JobClient client = new JobClient(job);
	ClusterStatus cluster = client.getClusterStatus();
	return cluster.getMaxMapTasks();
}