PCIE TRAFFIC TRACKING HARDWARE IN A UNIFIED VIRTUAL MEMORY SYSTEM

摘要

Techniques are disclosed for tracking memory page accesses in a unified virtual memory system. An access tracking unit detects a memory page access generated by a first processor for accessing a memory page in a memory system of a second processor. The access tracking unit determines whether a cache memory includes an entry for the memory page. If so, then the access tracking unit increments an associated access counter. Otherwise, the access tracking unit attempts to find an unused entry in the cache memory that is available for allocation. If so, then the access tracking unit associates the second entry with the memory page, and sets an access counter associated with the second entry to an initial value. Otherwise, the access tracking unit selects a valid entry in the cache memory; clears an associated valid bit; associates the entry with the memory page; and initializes an associated access counter.

主权项

1. A computer-implemented method for tracking memory page accesses in a unified virtual memory system, the method comprising:
detecting a memory page access generated by a first processor for accessing a memory page in a memory system that is associated with a second processor; determining whether a cache memory associated with the first processor includes a first entry corresponding to an address associated with the memory page; if the cache memory includes the first entry, then:
incrementing an access counter associated with the first entry that counts accesses of the memory page; or if the cache memory does not include the first entry, then:
initializing a second entry in the cache memory to correspond to the memory page.