Cache design of a sub-micron CMOS system/370

Abstract

An innovative cache accessing scheme based on high MRU (most recently used) hit ratio [1] is proposed for the design of a one-cycle cache in a CMOS implementation of System/370. It is shown that with this scheme the cache access time is reduced by 30 ~ 35% and the performance is within 4% of a true one-cycle cache. This cache scheme is proposed to be used in a VLSI System/370, which is organized to achieve high performance by taking advantage of the performance and integration level of an advanced CMOS technology with half-micron channel length [2]. Decisions on the system partition are based on technology limitations, performance considerations and future extendability. Design decisions on various aspects of the cache organization are based on trace simulations for both UP (uniprocessor) and MP (multiprocessor) configurations.