X-Git-Url: http://mj.ucw.cz/gitweb/?a=blobdiff_plain;f=lib%2Fsorter%2FTODO;h=f4a802cacbceb191459a33a6bcd864a95aab51e6;hb=556cfa14c25a4124673e2a7489308e82021cf58b;hp=5b848ef0557c5ff5196d251e50507e8db1772a35;hpb=df047d308d980b9822ed05230cc3dbbafc28da0b;p=libucw.git diff --git a/lib/sorter/TODO b/lib/sorter/TODO index 5b848ef0..f4a802ca 100644 --- a/lib/sorter/TODO +++ b/lib/sorter/TODO @@ -4,16 +4,12 @@ o Records of odd lengths. o Empty files. Improvements: -o Alignment? Use of SSE? 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 Implement multi-way merge. -o Mode with only 2-way unification? -o Speed up 2-way merge. -o Speed up radix splitting. -o A debug switch for disabling the presorter. o Deal with too rough range estimates in radix splitting. +o How does the speed of radix splitting decrease with increasing number of hash bits? + Does it help to use more bits than we need, so that we sort less data in memory? +o Log messages should show both original and new size of the data. The speed + should be probably calculated from the former.