METHOD, PROGRAM, AND SYSTEM FOR REDUCING THE COST OF STACK SCANNING

摘要

A method for reducing the cost of stack scanning in garbage collection (GC) includes, in the GC of the first-generation heap area, registering, in a nursery object reference list prepared for each thread, one or more addresses, within each stack, which each refer to a nursery object, and updating a scanning unnecessary area starting pointer such that the addresses listed in the nursery object reference list are included in the area from the bottom of the stack to the address pointed to by the scanning unnecessary area starting pointer. The method further includes, in the next GC of the first-generation heap area, for the area from the bottom of the stack to the address pointed to by the scanning unnecessary area starting pointer, performing the GC processing on the addresses included in the nursery object reference list.

主权项

1. A method, implemented by a computer system supporting generational garbage collection (GC), for reducing the cost of stack scanning, the method comprising:
for each thread, preparing, using a hardware processor, a scanning unnecessary area starting pointer pointing to inside a stack of the thread; in a GC of a first-generation heap area, setting a value for the scanning unnecessary area starting pointer for each thread such that an area from a bottom of the stack to an address pointed to by the scanning unnecessary area starting pointer becomes an area which includes no reference to a nursery object residing in the first-generation heap area; and in a next GC of the first-generation heap area, performing stack scanning, for each thread, on only stack frames located above a stack frame pointed to by the scanning unnecessary area starting pointer.