public TaskTracker() {
		this.maxMapSlot = Configuration.MAP_PER_NODE;
		this.maxReduceSlot = Configuration.REDUCE_PER_NODE;
		this.mapTasks = new ArrayDeque<MapTask>(maxMapSlot);
		this.reduceTasks = new ArrayDeque<ReduceTask>(maxReduceSlot);
		this.finishedTasks = new ArrayDeque<Task>();
		this.partition = new HashMap<Integer, HashMap<Integer, ArrayDeque<String[]>>>();
		this.slaveList = new HashMap<Integer, String>();
		this.dfs = new DFSClient();
	}