Hi there, I'm getting confused of the run-time system behavior of GUM. When I ran a quicksort program in GUM with profiling flag, I got different "task" distributions in the PS file generated everytime, e.g., the peak of task number may be 19 at the first time and 48 at the second. While it's quite reasonable that the clock cycles vary dramatically, it's somewhat strange to me that the task distributions are so different. Any hints? I do appreaciate it. BTW, seems the program does not stop if the input list has more than 350 elements, althought it works fine otherwise. Will it get better if I use an SMP system? Thanks in advance. PS: I'm using GUM-4.06, PVM3, RH LINUX6.2 on a single processor system. Program and RTS flags quicksort +RTS -qP -sstderr grs2gr *quicksort.???.gr > quicksort.gr gr2ps -o quicksort.ps quicksort.gr --source code module Main(main) where import System(getArgs) import Parallel forceList :: [a] -> () forceList [] = () forceList (x:xs) = x `seq` forceList xs quicksortF::[Int]->[Int] quicksortF [] = [] quicksortF [x] = [x] quicksortF (x:xs) = (forceList losort) `par` (forceList hisort) `par` losort ++ (x:hisort) where losort = quicksortF [y|y <- xs, y < x] hisort = quicksortF [y|y <- xs, y >= x] args_to_IntList :: [String] -> [Int] args_to_IntList a = if length a < 1 then error "Parallel Quick Sort: no enough args \n" else map read a main = putStr ("get " ++ (show (quicksortF l))++"\n") l = [ 658986,123141,737929,681645,329651, ... 925104]