US 12,487,924 B2 · Concurrent lazy reference counting in an old garbage collection generation

Abstract

Techniques for concurrent lazy reference tracking in an old garbage collection generation are disclosed, including: encountering, by a mutator thread during a garbage collection epoch, a first instruction to write a first value to a field; responsive to encountering the first instruction to write the first value to the field: entering a slow-path write barrier; performing, by the slow-path write barrier, a first one or more reference counting operations with respect to the field; encountering, by the mutator thread during the first garbage collection epoch and subsequent to encountering the first instruction to write the first value to the field, a second instruction to write a second value to the field; responsive to encountering the second instruction to write the second value to the field: entering a fast-path write barrier; wherein the fast-path write barrier does not perform any reference counting operations with respect to the field.

Claims20

Dependent claims

One or more non-transitory computer-readable media storing instructions which, when executed by one or more hardware processors, cause performance of operations comprising:

encountering, by a mutator thread during a first garbage collection epoch, a first instruction to write a first value to a field;
responsive to encountering the first instruction to write the first value to the field:
entering a slow-path write barrier;
performing, by the slow-path write barrier, a first one or more reference counting operations with respect to the field;
encountering, by the mutator thread during the first garbage collection epoch and subsequent to encountering the first instruction to write the first value to the field, a second instruction to write a second value to the field;
responsive to encountering the second instruction to write the second value to the field:
entering a fast-path write barrier;
wherein the fast-path write barrier does not perform any reference counting operations with respect to the field.

5 more elements

A system comprising:

one or more hardware processors;
one or more non-transitory computer-readable media;
and
program instructions stored on the one or more non-transitory computer readable media which, when executed by the one or more hardware processors, cause the system to perform operations comprising:
encountering, by a mutator thread during a first garbage collection epoch, a first instruction to write a first value to a field;
responsive to encountering the first instruction to write the first value to the field:
entering a slow-path write barrier;
performing, by the slow-path write barrier, a first one or more reference counting operations with respect to the field;
encountering, by the mutator thread during the first garbage collection epoch and subsequent to encountering the first instruction to write the first value to the field, a second instruction to write a second value to the field;
responsive to encountering the second instruction to write the second value to the field:
entering a fast-path write barrier;
wherein the fast-path write barrier does not perform any reference counting operations with respect to the field.

9 more elements

Dependencies are inferred from the claim text.

Concurrent lazy reference counting in an old garbage collection generation

Life of this patent

Concurrent lazy reference counting in an old garbage collection generation

Life of this patent

Abstract

Claims20