An estimate of the throughput of a multi-threaded processor based on measured miss rates of a cache memory associated with the processor is adjusted to account for cache miss processing delays due to memory bus access contention. In particular, the throughput calculated from the cache memory miss rates is initially calculated assuming that a memory bus between the cache memory and main memory has infinite bandwidth, this throughput estimate is used to estimate a request cycle time between memory access attempts for a typical thread. The request cycle time, in turn, is used to determine a memory bus access delay that is then used to adjust the initial processor throughput estimate. The adjusted estimate can be used for thread scheduling in a multiprocessor system.