Title
Synergistic design of an application-oriented sparse directory on many-core embedded systems.
Abstract
As many-core embedded systems are evolving from single-memory based designs to systems-on-a-chip running on an on-chip network, implementing a cache coherence mechanism in large-scale many-core embedded systems turns out to be a technical challenge. However, existing coherence mechanisms are difficult to scale beyond tens of cores, which require either excessive area or energy, complex hierarchical protocols, or inexact representations of sharer sets. In this paper, we present a hardware-software synergistic design of a cache coherence mechanism by considering OS-level application allocation and hardware-level coherence operations. The proposed application-oriented sparse directory (AoSD) cooperates with a contiguous allocation algorithm to isolate cache coherence traffic and thereby reduce interferences among applications. The proposed micro-architecture of sharer set representations is area-efficient; moreover, it can also be configured dynamically to track a flexible and exact sharer set. We verify our design by analyzing memory requirements of different cache organizations and implementing our design on a popular simulator Graphite to evaluate cache coherence traffic improvement. The results show that our design is both area-efficient and efficient with improvements in memory network performance by 11.74%–28.72%. It is also indicated that our design is feasible to scale up to work well in thousands-of-cores embedded systems.
Year
DOI
Venue
2017
10.1016/j.sysarc.2017.10.006
Journal of Systems Architecture
Keywords
Field
DocType
Hardware-software synergy,Many-core embedded systems,Application-oriented sparse directory,Thousands of cores,Dynamic application allocation
Cache invalidation,Computer science,Cache,Real-time computing,Cache coloring,Distributed computing,Parallel computing,Coherence (physics),Cache algorithms,Bus sniffing,Network performance,Cache coherence,Embedded system
Journal
Volume
ISSN
Citations 
81
1383-7621
1
PageRank 
References 
Authors
0.37
24
5
Name
Order
Citations
PageRank
chang wang13312.55
Yongxin Zhu246658.07
Victor Chang31202107.48
Jiang Jiang4102.58
Han Song513.07