US Patent 11599473 Methods and apparatus for training prefetch information

Aspects of the present disclosure relate to an apparatus comprising prefetch information storage circuitry and prefetch training circuitry. The prefetch training circuitry comprises a plurality of entries, and is configured to: allocate a given entry to a given data address region; receive access information indicative of data accesses within the given data address region; based on said access information, train prefetch information associated with the given data address region, the prefetch information being indicative of a pattern of said data accesses within the given data address region; and responsive to an eviction condition being met after an elapsed period, since said allocation of the given entry, has exceeded a threshold, perform an eviction comprising transferring the prefetch information associated with the given data address region to the prefetch information storage circuitry.