Complementary garbage collector

Abstract

This paper describes the design and evaluation of a Complementary Garbage Collector that is a fundamental algorithm for parallel and incremental garbage collection. Our algorithm is a combination of two types of fundamental algorithms, incremental update and snapshot-at-beginning, which are complementary to each other. The algorithm has the advantages of both types: greater efficiency of garbage collection and ease of consistent implementation. This algorithm can be substituted for the snapshot-at-beginning algorithm widely used in several types of parallel and incremental garbage collectors. Measurements of this algorithm in a parallel and an incremental mark-sweep GC indicate that it improves the efficiency of the collection making it equivalent to a stop-and-collect garbage collector. Consequently, the execution time of the list processing is shortened and the range of non-stop processing is extended.