Storage System Hierarchy and Process Data Storage Model

摘要

In a computer system, the storage devices, including registers, caches, main memory and exterior devices, are organized as a hierarchical system. In the traditional operating systems, there are two data storage models, one is process virtual address space that is constructed at the level of main memory, the other is file that is constructed at the level of exterior storage devices. There is no data storage model that is constructed at the level of registers or caches. We believe it unnecessary to construct the process virtual address space, there should exist only one data storage model--the abstract file, which is constructed upon exterior devices, main memory should be used as file buffer, instructions access files directly and processes run upon files. Basing on these ideas, we propose an operating system model. It constructs only one data storage model-the abstract file, which is unique, of single address space, persistent, and distributed. In this operating system, users see no virtual process address space, instructions access files directly, and all processes run on files. That is the reason why we call it No Address Space Operating System-NASOS.