costEstimator.addLocalSortCost(e2, mm1);
costEstimator.addLocalMergeCost(e1, e2, mm1, 1);
costEstimator.addLocalSortCost(e1, mm5);
costEstimator.addLocalSortCost(e2, mm5);
mm5.multiplyWith(5);
costEstimator.addLocalMergeCost(e1, e2, mm5, 5);
// weight 1 versus weight 5
assertTrue(hf1.compareTo(hf5) < 0);
assertTrue(hs1.compareTo(hs5) < 0);