@Override
  public List<InputSplit> getSplits(JobContext context) throws IOException {
    try {
      // Do a round robin on what we get back from the super-class.
      configure();
      return roundRobin(getSuperSplits(context));
    } finally {
      unconfigure();
    }
  }
Boolean config for whether superclass should produce InputSplits with 'lengths'. If true, TIF
will query every RegionServer to get the 'size' of all involved Regions and this 'size' will be
used the the InputSplit length. If false, we skip this query and the super-classes returned
InputSplits will have lenghths of zero. This override will set the flag to false. All returned
lengths will be zero. Makes it so sorting on 'length' becomes a noop. The sort returned by this
override will prevail. Thats what we want.
hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/RoundRobinTableInputFormat.java