Performance estimates for supercomputers: The responsibilities of the manufacturer and of the user

As an alternative to benchmarks two other methods for the evaluation of the performance of supercomputers are discussed. Micro-measurements reveal the sources for lost cycles for an individual operation. For this purpose we present measurements of the vector triad for the IBM 3090 VF and CRAY Y-MP. A global performance formula gives an estimate for the expected overall performance of a single processor or multiprocessor supercomputer. The formula factorizes the individual losses and makes clearly visible the responsibilities of the manufacturer and of the user for these losses.