Patent ID: 6173294
Filing Date: 2001-01-09
Classification: G06F,Y10S

Abstract:
A computer-implemented method for performing garbage collection of memory objects in a memory heap, the method comprising the steps of:(a) partitioning said heap or a portion thereof into at least three generations; a generation from among said at least three generations constituting oldest generation and being least frequently subject to garbage collection, other generations from among said at least three generations constituting younger generations of which one constitutes a youngest generation most frequently subject to garbage collection;(b) partitioning said heap or partition thereof into cards;(c) associating said generations with remembered sets and card markings data structures; said card marking including, for each card, a card scan indication indicative of a youngest one of said generations for which the card has not been scanned;(d) for every card having a card scan indication value that does not exceed a selected generation;i. identifying updated inter-generational pointers that refer to memory objects that reside in said selected generation or younger generations;ii. updating the respective remembered set with the identified inter-generational pointers for each identified updated inter-generational pointer; andiii. updating the card scan indication of said card to a generation older by one than said selected generation.