A virtual memory system design
O. R. Pardo · NASA STI Repository (National Aeronautics and Space Administration) · 1971
Ab s tract This paper describes a virtual memory management system based upon the working set model t.hat is suitable for microprogramming. As in-troiuction, several current systems employing virtual memory are briefly described, and the working set strategy, the task scheduling/memory manage-ment algorithm, and the concept of a paging drum are introduced. The paper then presents, in ' detail, the hardware and software coxportents of a virtual meniory management system. The hardware components which are described in CDI, include the rrain memory, the translation menory, the page table memory, and the paging drum channel. The software components are described in ALGOL and interfacea with the hardware by defining registers a8 global var-iables and referring to hardware sequences through procedure calls. The software description includes complete description of the addressing mechan-ism, memory management, and task scheduling. Memory management is enhanced by the use of a page-table memory that posts the current status of each