TRENDS IN DIGITAL COMPUTER SYSTEM ARCHITECTURE

Abstract

Computer system architecture has been and always will be significantly influenced by the underlying trends and capabilities of hardware and software technologies. This transition from electromechanical relays to vacuum tubes to transistor to integrated circuits has driven fundamentally different trade-off in the architecture of computer systems (Groves, 1998). Additional advances in software, which include the transition of the predominant approach to programming from machine language to high level procedural language to object-oriented language have also resulted in new capabilities and design points. In this thesis, The trends in computer system architecture from pre-Von Neumann to the present state of the art in computer system architecture were examined and comparatively analyzed. Also the influence of computer application and technologies on computer system architectures past, present and future are explored and projected. It is observed that in Von Neumann architectures, starting from Complex instruction set computer (CISC) to Reduced instruction set computer (RiSe) to Transport triggered architecture (TTA) , speed enhancement techniques like pipelining, superpipelining, superscalar, multiple data/instruction paths were employed. These techniques enable single cycle/ dynamic execution of multiple instructions. In addition, RISC and Superscalars techniques were found to shift most of their responsibilities to the hardware, while VLlWs and TTA relied on compiler to perform most of the tasks. Non Von Neumann architectures like X-puters added a new hardware efficiency, it uses a data-sequencer (instead of an instruction sequencer) including a powerful address generator to avoid addressing overhead, control flow overhead and other kinds of overhead which eats up most of the throughput and primary memory bandwidth in Von Neumann architectures. Advances in technology and design techniques have produced intel's Xeon processor MP running at 2.40Ghz and seagate's Barracuda7200 HOD with 160GB capacity which is a tremendous achievement. Advances in networking has also turned the world into a global village, and has made a number of interesting services available to the public.