Cost-effective object space management for hardware-assisted real-time garbage collection

Abstract

Modern object-oriented languages and programming paradigms require finer-grain division of memory than is provided by traditional paging and segmentation systems. This paper describes the design of an OSM (Object Space Manager) that allows partitioning of real memory on object, rather than page, boundaries. The time required by the OSM to create an object, or to find the beginning of an object given a pointer to any location within it, is approximately one memory cycle. Object sizes are limited only by the availability of address bits. In typical configurations of object-oriented memory modules, one OSM chip is required for every 16 RAM chips. The OSM serves a central role in the implementation of a hardware-assisted garbage collection system in which the worst-case stop-and-wait garbage collection delay ranges between 10 and 500 μsec, depending on the system configuration.