International Business Machines Corporation
Prefetch queue allocation protection bubble in a processor

Abstract:

A computer system, processor, and method for processing information is disclosed that includes allocating a prefetch stream; providing a protection bubble to a plurality of cachelines for the allocated prefetch stream; accessing a cacheline; and preventing allocation of a different prefetch stream if the accessed cacheline is within the protection bubble. The system, processor and method in an aspect further includes providing a safety zone to a plurality of cachelines for the allocated prefetch stream, and advancing the prefetch stream if the accessed cacheline is one of the plurality of cachelines in the safety zone. In an embodiment, the number of cachelines within the safety zone is less than the number of cachelines in the protection bubble.