apache/hadoop · error · IllegalArgumentException

taskType can only be MAP:

Error message

taskType can only be MAP: 

What it means

Error "taskType can only be MAP: " thrown in apache/hadoop.

Source

Thrown at hadoop-tools/hadoop-rumen/src/main/java/org/apache/hadoop/tools/rumen/ZombieJob.java:547

      double rackLocalOverNodeLocal, double rackRemoteOverNodeLocal) {
    TaskInfo taskInfo = getTaskInfo(loggedTask);
    double[] factors = new double[] { 1.0, rackLocalOverNodeLocal,
        rackRemoteOverNodeLocal };
    double scaleFactor = factors[locality] / factors[loggedLocality];
    State state = convertState(loggedAttempt.getResult());
    if (loggedTask.getTaskType() == Values.MAP) {
      long taskTime = 0;
      if (loggedAttempt.getStartTime() == 0) {
        taskTime = makeUpMapRuntime(state, locality);
      } else {
        taskTime = loggedAttempt.getFinishTime() - loggedAttempt.getStartTime();
      }
      taskTime = sanitizeTaskRuntime(taskTime, loggedAttempt.getAttemptID());
      taskTime *= scaleFactor;
      return new MapTaskAttemptInfo
        (state, taskInfo, taskTime, loggedAttempt.allSplitVectors());
    } else {
      throw new IllegalArgumentException("taskType can only be MAP: "
          + loggedTask.getTaskType());
    }
  }

  private int getLocality(LoggedTask loggedTask, LoggedTaskAttempt loggedAttempt) {
    int distance = cluster.getMaximumDistance();
    String rackHostName = loggedAttempt.getHostName().getValue();
    if (rackHostName == null) {
      return distance;
    }
    MachineNode mn = getMachineNode(rackHostName);
    if (mn == null) {
      return distance;
    }
    List<LoggedLocation> locations = loggedTask.getPreferredLocations();
    if (locations != null) {
      for (LoggedLocation location : locations) {
        List<NodeName> layers = location.getLayers();

View on GitHub (pinned to 2add963021)

Solutions

1. Only call this map-specific path for MAP task types; the taskType in the trace differs.

When it happens

Trigger: getFirstJob/getMapAttempt-related logic is invoked for a task whose type is not MAP, violating the caller's assumption.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/4948056437521e9e. Report an issue: GitHub.