Patent ID: 7039664

Claim:
For operating a computer system including memory as a garbage collector, a method comprising: A) providing a computer system that includes memory; B) configuring the computer system to operate as a garbage collector that: i) treats at least a portion of a garbage-collected heap in the memory as divided into cards with which the garbage collector associates respective card-object-table entries; ii) maintains the card-object-table entries; iii) determines whether a multiple-card-object-table-entry sequence that includes the card-object-table entry with which a given card is associated satisfies a predetermined common-object criterion; iv) if that multiple-card-object-table-entry sequence is thereby determined to satisfy the common-object criterion, interprets that multiple-card-object-entry sequence as an indicator of the location at which is located a predetermined field of an object in which a predetermined location in the given card is located; v) if that multiple-card-object-table-entry sequence is thereby determined not to satisfy the common-object criterion, interprets the card-object-table entry with which the given card is associated as locator information maintained by the collector for the given card; vi) bases on that interpretation a determination of which locations in the card contain references; vii) determines the reachability of objects from the contents of locations thereby determined to be references; and viii) reclaims memory space occupied by objects thereby determined not to be potentially reachable; and C) causing the computer system to operate as the garbage collector as which it is thereby configured.