Extension of the PDP-11 Address Space

This document, a technical memorandum from 1970, examines the limitations of the 16K word address space in the PDP-11 architecture. It compares the PDP-11 with other medium-sized computers, analyzes the market requirements for larger address spaces in both single-user and time-sharing environments, and evaluates the viability of memory expansion techniques such as paging and segmentation. The author concludes that these techniques, while technically feasible, do not provide an efficient solution for the PDP-11 to handle the large programs required by the intended 32-bit competitive class, ultimately recommending against their implementation for this specific architecture.