Multi-tiered Cache Management for E-Commerce Web Sites

Response time is a key differentiation point among electronic commerce (e-commerce) applications. For many e-commerce applications, Web pages are created dynamically based on the current state of a business stored in database systems. To improve the response time, many e-commerce Web sites deploy caching solutions for acceleration of content delivery. There are multiple tiers in the content delivery infrastructure where cache servers can be deployed, including (1) data caching (in data centers), (2) content page caching (in edge or frontend caches), (3) database query result set caching (between application servers and DBMS). The architecture of database-driven e-commerce Web sites is more complex than that of typical Web sites. It requires the integration of Web servers, application servers, and back-end database systems as well as dynamic content caching solutions. In this paper, we study issues associated with management of content page caching and database query result set caching tiers. We observe that caching management for these two tiers have their unique characteristics. It is because cached object types and information available for the caching management in the two tiers are different. We propose solutions for effective caching management for each tier and conduct extensive evaluations. The experiment results show the usefulness of our technology in improving overall system performance.