Memory Systems

3.3 Case Studies: Combined Approaches

There are numerous examples of schemes that fashion a synergy between on-line and off-line mechanisms. These are schemes where the two cooperate to exploit the opportunities available on each side. The off-line mechanism exploits knowledge of the application code and provides information to the online mechanism, which can exploit dynamic information such as memory disambiguation.

A simple example is the PA-7200’s spatial locality only cache hint for load/store instructions [Chan et al. 1996]. This mechanism indicates to the memory system that the corresponding data exhibits spatial locality, but not temporal locality; the data should not necessarily be found in or placed in the regular cache hierarchy. ...