Multiprocessor system bus with combined snoop responses explicitly cancelling master allocation of read data

Abstract

In cancelling the cast out portion of a combined operation including a data access related to the cast out, the combined response logic explicitly directs the storage device initiating the combined operation not to allocate storage for the target of the data access. Instead, the target of the data access may be passed directly to an in-line processor core without storage, may be stored in a horizontal storage device, or may be stored in an in-line, noninclusive, lower level storage device. Cancellation of the cast out thus defers any latency associated with writing the cast out victim to system memory while maximizing utilization of available storage with acceptable tradeoffs in data access latency.

Dependencies are inferred from the claim text.