Disk-Offload Middleware for Web-Services Using the Application-Caching Paradigm

Application-caching occurs when applications assume control for data caching rather then relying on middleware to manage their data. This paradigm is a good fit for"main-memory caching" in which data storage and retrieval issues are relatively straight-forward. However, the caching requirements of certain workloads exceed even modern main-memory capacity. Although disk-offload offers the potential to overcome this capacity constraint, it poses a problem for the application-caching paradigm since application data may now be resident in either main-memory or on disk. In this paper, we therefore examine how disk-offload middleware can best support the application-caching paradigm for data-centric web-services. We present two disk-offload caching architectures, evaluate their performance, and draw conclusions as to their relative effectiveness.