Cache Coherency in Distributed File System

International Journal of Computer Science and Security 01/2010;
Source: DOAJ

ABSTRACT Principle of locality states that most memory references are made to a smallnumber of memory locations. Not only that, memory locations near most recentlyreferenced locations are more likely to be referenced than one further away. Totake advantage of this, cache memory is inserted between memory and CPU [1].Better utilization of cache is crucial for good performance of distributed filesystem; even in case of remote file accesses.Not caching a file during writes prolongs the session, thereby increasing writesharingtime, leading to slow performance especially on WANs. This paperintroduces a technique to reduce miss penalty during remote file writes andallows write sharing in LAN. It uses the principle of divide-and-rule and arrangesthe system into hierarchical domains and then gives ownerships to the writers.

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