THE STRUCTURE OF A LISP SYSTEM USING TWO-LEVEL STORAGE, SCIENTIFIC REPORT

In an ideal list-processing system there would be enough core memory to contain all the data and programs. The paper describes a number of techniques used to build a LISP system which utilizes a drum for its principal storage medium, with a surprisingly low time-penalty for use of this slow storage device. The techniques include careful segmentation of system programs, allocation of virtual memory to allow address arithmetic for type determination, and a special algorithm for building reasonably linearized lists. A scheme is described for binding variables which is good in this environment and allows for complete compatibility between compiled and interpreted programs with no special declarations.