Package org.apache.hadoop.mapred

Class ClusterStatus

java.lang.Object
org.apache.hadoop.mapred.ClusterStatus
All Implemented Interfaces:
Writable
@Public @Stable public class ClusterStatus extends Object implements Writable
Status information on the current state of the Map-Reduce cluster.

ClusterStatus provides clients with information such as:

  1. Size of the cluster.
  2. Name of the trackers.
  3. Task capacity of the cluster.
  4. The number of currently running map and reduce tasks.
  5. State of the JobTracker.
  6. Details regarding black listed trackers.

Clients can query for the latest ClusterStatus, via JobClient.getClusterStatus().

See Also:

  • Field Details

    • UNINITIALIZED_MEMORY_VALUE

      public static final long UNINITIALIZED_MEMORY_VALUE
      See Also:

  • Method Details

    • getTaskTrackers

      public int getTaskTrackers()
      Get the number of task trackers in the cluster.
      Returns:
      the number of task trackers in the cluster.

    • getActiveTrackerNames

      public Collection<String> getActiveTrackerNames()
      Get the names of task trackers in the cluster.
      Returns:
      the active task trackers in the cluster.

    • getBlacklistedTrackerNames

      public Collection<String> getBlacklistedTrackerNames()
      Get the names of task trackers in the cluster.
      Returns:
      the blacklisted task trackers in the cluster.

    • getGraylistedTrackerNames

      @Deprecated public Collection<String> getGraylistedTrackerNames()
      Deprecated.
      Get the names of graylisted task trackers in the cluster. The gray list of trackers is no longer available on M/R 2.x. The function is kept to be compatible with M/R 1.x applications.
      Returns:
      an empty graylisted task trackers in the cluster.

    • getGraylistedTrackers

      @Deprecated public int getGraylistedTrackers()
      Deprecated.
      Get the number of graylisted task trackers in the cluster. The gray list of trackers is no longer available on M/R 2.x. The function is kept to be compatible with M/R 1.x applications.
      Returns:
      0 graylisted task trackers in the cluster.

    • getBlacklistedTrackers

      public int getBlacklistedTrackers()
      Get the number of blacklisted task trackers in the cluster.
      Returns:
      the number of blacklisted task trackers in the cluster.

    • getNumExcludedNodes

      public int getNumExcludedNodes()
      Get the number of excluded hosts in the cluster.
      Returns:
      the number of excluded hosts in the cluster.

    • getTTExpiryInterval

      public long getTTExpiryInterval()
      Get the tasktracker expiry interval for the cluster
      Returns:
      the expiry interval in msec

    • getMapTasks

      public int getMapTasks()
      Get the number of currently running map tasks in the cluster.
      Returns:
      the number of currently running map tasks in the cluster.

    • getReduceTasks

      public int getReduceTasks()
      Get the number of currently running reduce tasks in the cluster.
      Returns:
      the number of currently running reduce tasks in the cluster.

    • getMaxMapTasks

      public int getMaxMapTasks()
      Get the maximum capacity for running map tasks in the cluster.
      Returns:
      the maximum capacity for running map tasks in the cluster.

    • getMaxReduceTasks

      public int getMaxReduceTasks()
      Get the maximum capacity for running reduce tasks in the cluster.
      Returns:
      the maximum capacity for running reduce tasks in the cluster.

    • getJobTrackerStatus

      public Cluster.JobTrackerStatus getJobTrackerStatus()
      Get the JobTracker's status.
      Returns:
      Cluster.JobTrackerStatus of the JobTracker

    • getMaxMemory

      @Deprecated public long getMaxMemory()
      Deprecated.
      Returns UNINITIALIZED_MEMORY_VALUE (-1)

    • getUsedMemory

      @Deprecated public long getUsedMemory()
      Deprecated.
      Returns UNINITIALIZED_MEMORY_VALUE (-1)

    • getBlackListedTrackersInfo

      public Collection<org.apache.hadoop.mapred.ClusterStatus.BlackListInfo> getBlackListedTrackersInfo()
      Gets the list of blacklisted trackers along with reasons for blacklisting.
      Returns:
      the collection of ClusterStatus.BlackListInfo objects.

    • getJobTrackerState

      @Deprecated public JobTracker.State getJobTrackerState()
      Deprecated.
      Get the current state of the JobTracker, as JobTracker.State JobTracker.State should no longer be used on M/R 2.x. The function is kept to be compatible with M/R 1.x applications.
      Returns:
      the invalid state of the JobTracker.

    • write

      public void write(DataOutput out) throws IOException
      Description copied from interface: Writable
      Serialize the fields of this object to out.
      Specified by:
      write in interface Writable
      Parameters:
      out - DataOuput to serialize this object into.
      Throws:
      IOException - any other problem for write.

    • readFields

      public void readFields(DataInput in) throws IOException
      Description copied from interface: Writable
      Deserialize the fields of this object from in.

      For efficiency, implementations should attempt to re-use storage in the existing object where possible.

      Specified by:
      readFields in interface Writable
      Parameters:
      in - DataInput to deseriablize this object from.
      Throws:
      IOException - any other problem for readFields.