Abstract not found

We describe our implementation of several PRAM graph algorithms on the massively parallel computer MasPar MP-1 with 16,384 processors. Our implementation incorporated virtual processing and we present extensive test data. In a previous project [13], we reported the implementation of a set of parallel graph algorithms with the constraint that the maximum input size was restricted to be no more than the physical number of processors on the MasPar. The MasPar language MPL that we used for our code does not support virtual processing. In this paper, we describe a method of simulating virtual processors on the MasPar. We re-coded and fine-tuned our earlier parallel graph algorithms to incorporate the usage of virtual processors. Under the current implementation scheme, there is no limit on the number of virtual processors that one can use in the program as long as there is enough main memory to store all the data required during the computation. We also give two general optimization techniq...

We describe our implementation of several efficient parallel algorithms on the massively parallel SIMD machine MasPar MP-1 with virtual processing. The MPL language that we used on the MasPar MP-1 does not support virtual processing. In this paper, we describe the implementation of virtual processing for several combinatorial algorithms using the MPL language. We present our data allocation scheme for virtual processing and code rewriting rules for converting a code that uses no virtual processors into a code with virtual processing. We then describe the implementation of virtual processing and the fine-tuning of a set of commonly used routines. In coding these routines, we tried different underlying (deterministic and randomized) algorithms. We present the performance data for our different implementations. We also compared the performance of several of the parallel routines with their sequential implementations. The performance of our code tracks theoretical predictions quite well fo...