-Testing:
-o Giant runs.
-o Records of odd lengths.
-o Empty files.
+Cleanups:
+o Log messages should show both original and new size of the data. The speed
+ should be probably calculated from the former.
+o Buffer sizing in shep-export.
Improvements:
-o Use radix-sort for internal sorting.
-o Parallelization of internal sorting.
-o Clean up data types and make sure they cannot overflow. (size_t vs. u64 vs. sh_off_t vs. uns)
-o Buffer sizing in internal sorters.
-o Switching between direct and normal I/O.
-o When merging, choose the output file with less runs instead of always switching?
-o Deal with too rough range estimates in radix splitting.
+o When quicksorting a large input (especially in threaded case), invest more
+ time to picking a good pivot.
+o Overlay presorter I/O with internal sorting.
+
+Users of lib/sorter/array.h which might use radix-sorting:
+indexer/chewer.c
+indexer/lexfreq.c
+indexer/mkgraph.c
+indexer/reftexts.c