Systems and methods for directory based cache coherence

Abstract

A system for memory management accessible by a plurality of computing units, comprises: an interface adapted to receive a request to access one of a plurality of storage regions of a cache storage; and a memory for storing: a single access 5 directory documenting which of the plurality of storage regions is currently assigned to one of the plurality of computing units; and a multi-access directorydocumenting which of the plurality of storage regions is accessed by at least one of a plurality of computing units.

Description

Background technique [0001] Some embodiments of the invention relate to cache coherency, and more particularly, but not exclusively, to systems and methods for directory-based cache coherency. [0002] In a multiprocessing system including multiple processing units, a cache coherency protocol maintains coherency between local caches (each associated with a processing unit) and shared memory (accessible to all processing units). Directory-based cache coherency protocols are based on a common directory that maintains consistency between local caches. This directory keeps track of shared memory blocks stored in the local cache. A directory-based cache coherency protocol can provide local processors with fast and consistent access to shared memory without broadcasting requests to all local caches. [0003] As the number of processing units and corresponding local caches increases in a multiprocessing system and / or the size of the local cache increases, the cache eviction rate ma...

AI Technical Summary

Problems solved by technology

However, such solutions may not provide precise tracking and may require additional snooping mechanisms, consistency recovery mechanisms, or broadcast and refresh based page eviction mechanisms

These mechanisms may degrade the performance of the public directory, and / or may not be scalable

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