Adaptive Fast Path Architecture

Adaptive Fast Path Architecture (AFPA) is a software architecture that dram atically improves the efficiency, and therefore the capacity, of Web and ot her network sewers. The architecture includes a RAM-based cache that serves static content and a reverse proxy that can distribute requests for dynami c content to multiple servers. These two mechanisms are combined using a fl exible layer-7 (content-based) routing facility, The architecture defines i nterfaces that allow these generic mechanisms to be exploited to accelerate a variety of application protocols, including HTTP, Efficiency is derived from maximizing the number of requests that are handled entirely within the kernel, using a deferred-interrupt context instead of threads wherever pos sible. AFPA has been implemented on several server platforms including Micr osoft Windows NT(R) and Windows((R)) 2000, OS/390((R)), AIX((R)), and most recently Linux, By conservative estimates, AFPA more than doubles capacity for sewing static content compared to conventional server architectures, an d has allowed IBM to establish a leadership position in Web server performa nce. A prototype implementation of AFPA on Linux delivers more than 10000 S PECweb96 operations per second on a single processor.