Patent ID: 7412580

Claim:
A method for tracking and summarizing modified references in a garbage collector operating concurrently with applications, wherein a generation is partitioned in to a group of memory sections and wherein there are card table indicators associated with the group of memory sections storing if an application has written into or dirtied one or more of the memory sections, the method comprising the steps of: finding and atomically interrogating the indicators and finding at least one dirty indicator, resetting the at least one found dirty indicator to indicate not dirty, scanning the at least one dirtied memory section and updating the card table indicators or remembered sets of corresponding objects, wherein updating the card table indicators or remembered sets of corresponding objects comprises storing, in the card table indicators or remembered sets, at least one location of referencing objects that reference the corresponding objects, atomically interrogating the indicators again, and if none are dirty moving on to collect a next scheduled group of memory sections, and if at least one indicator is dirty, preserving the indicators as just interrogated before moving on to another group of memory sections distant from the next scheduled group.