The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 15, 2002
Filed:
Jun. 23, 1999
Richard J. Houldsworth, Horley, GB;
U.S. Philips Corporation, New York, NY (US);
Abstract
A method of garbage collection and data processing apparatus embodying the same. Within a heap memory, data objects are accessed via respective pointers carried by memory stacks; the memory is periodically swept to mark, for each object, a count of the number of extant pointers thereto from any source and, on detection that an object's count has reached zero, deleting that object. To permit concurrency of mark and sweep operations, a pair of reference count fields are maintained for each object: one holds an ongoing pointer count for the present mark operation and the other holds the value for the preceding one. At the conclusion of each mark operation, the mapping of counts into fields is reversed. An objects count is taken as zero, and the object deleted, when both counts are zero.