The Differences between Distributed Shared Memory Caching and Proxy Caching

performances.2–5 This article focuses on caching in two widely used types of sys-tems—distributed shared memory and proxy server systems—and stresses the main similarities and differences between these systems with regard to caching issues. This identifies possible caching mechanisms that we can improve by study-ing corresponding mechanisms on other types of systems. Terms DSM caching has been an active research area since the early 1980s and proxy caching since the early 1990s.6 In spite of the similarities between DSM and proxy caching, there are several remark-able differences that we can study from the point of view of the three major system lay-ers: architecture, organization, and design. In this article, the term architecture refers to the system’s functional structure, visible to the assembly language program-mer or the compiler. The term organiza-tion refers to how we can structure the global system to implement the character-istics the architecture imposes. Organiza-tion is transparent to the programmer, and there are many organizations for a given architecture. Finally, the term design is a concept closely related to implementation and technology; it refers to the internal structure of a given system resource. There are several designs in each organization. Criteria The criteria we will describe are not fully orthogonal because some criteria are related to others. We labeled each crite-rion according to the system layer to which it belongs: architecture (A), organization (O), or design (D). Criteria identifying properties of the application that use the system are labeled as property. GRANULARITY (O) Both DSM and proxy systems must carry out actions to maintain the shared The authors discuss the similarities in caching between the extensively studied distributed shared memory systems and the emerging proxy systems. They believe several techniques used in distributed shared memory systems can be adapted and applied to proxy systems