This paper shows how functional programming techniques have been successfully applied to relieve a performance bottleneck in an MPI collective communication operation. A functional speciication for the improved operation is given, and an eecient version implementable in an imperative language is derived and proved correct. Experimental results on an IBM SP2 distributed{memory machine connrm the...

Due to increased complexity and extreme quality of service requirements, traditional means for performance evaluation of telecom networks do not always suffice. The most flexible approach has been, and still is, simulation, which is the main focus of this paper. However, severe problems regarding efficiency exist, e.g. evaluation of ATM cell loss rate in range of <10-9 which is very computer in...