@Override
 protected RecordIterator doWork() {
   StackedComparator r = new StackedComparator(defs);
   QuickSort qs = new QuickSort();
   qs.sort(r, 0, records.size());
   return new OrderIterator();
 }
 public long doSort() {
   QuickSort qs = new QuickSort();
   ByteSortable b = new ByteSortable();
   long nano = System.nanoTime();
   qs.sort(b, 0, RECORD_COUNT);
   return System.nanoTime() - nano;
 }