Performance of cache coherence in stackable filing
John Heidemann, Gerald J. Popek · 1995
Stackable design of filing systems constructs sophisticated services from mukiple, independently developed layers.This approach has been advocated to address development problems from code re-use, to extensibility, to version management.Individual layers of such a system often need to cache data to improve performance orprovide desired functionality.Whenaccessto different layers isallowed, cache incoherencies can occur.Without a cache coherence solution, layer designers must either restrict layer access and flexibility or compromise the layered structure to avoid potential data corruption.Thevalue of modular designs such as stacking can be questioned without a suitable solution to this problem.This paper presents a general cache coherence architecture for stackable tiling, including a standard approach to data identifications a key component tolayered coherence protocols.We also present a detailed performance analysis of one implementation of stack cache-coherence, which suggests that very low overheads can be achieved in practice.