Incremental heap expansion in a real-time garbage collector

An apparatus for performing incremental garbage collection in a data processing system having memory spaces, a first of the memory spaces containing reachable and unreachable objects the apparatus comprising:

• a determination component configured to determine a size for a second of the memory spaces, the size being large enough to store the objects from the first of the memory spaces, and new objects to be allocated;
• an allocation component configured to allocate the second memory space so that the size of the second memory space is the determined size;
• and
• a copying component configured to simultaneously copy the reachable objects from the first memory space into the second memory space leaving the unreachable objects in the first memory space and allocate new objects in the second memory space.

A data processing system comprising:

• a memory further including:
• a computer program with an executing procedure for allocating reachable objects on a heap portion of the memory, wherein a plurality of the reachable objects become unreachable during the execution of the procedure;
• and
• an incremental garbage collector that iteratively performs garbage collection on the unreachable objects while allocating new objects and that dynamically resizes the heap portion of the memory during iterations of the garbage collection of the unreachable objects;
• and
• a processor for running the computer program and the garbage collector.

A method for performing incremental garbage collection in a data processing system having a procedure, a garbage collector, and memory spaces, a first of the memory spaces containing reachable and unreachable objects, the method comprising the steps of:

• starting execution of the procedure;
• determining a size for a second of the memory spaces by the garbage collector, the size being large enough to store the objects from the first of the memory spaces and new objects to be allocated;
• allocating the second memory space by the garbage collector such that the size of the second memory space is the determined size;
• copying by the garbage collector a root set from the first memory space into the second memory space, the root set capable of accessing the reachable objects.
• allocating new objects into the second memory space, and while each new object is allocated, copying by the garbage collector a predesignated portion of the reachable objects into the second memory space and leaving the unreachable objects in the first memory space until the reachable objects have been copied into the second memory space;
• discarding the first memory space by the garbage collector;
• and
• repetitively performing the foregoing steps until the procedure stops execution.

A computer-readable medium containing instructions for controlling a data processing system to perform an incremental garbage collection method, the data processing system having memory spaces, the method comprising the steps of:

• determining a size for a second of the memory spaces, the size being large enough to store the objects from the first of the memory spaces and new objects to be allocated;
• allocating the second memory space such that the size of the second memory space is the determined size;
• and
• simultaneously copying the reachable objects from the first memory space into the second memory space leaving the unreachable objects in the first memory space and allocating new objects in the second memory space.

An apparatus for performing incremental garbage collection in a data processing system having memory spaces, a first of the memory spaces containing reachable and unreachable objects, the apparatus comprising:

• a means for determining a size for a second of the memory spaces, the size being large enough to store the objects from the first of the memory spaces, and new objects to be allocated;
• a means for allocating the second memory space so that the size of the second memory space is the determined size;
• and
• a means for simultaneously copying the reachable objects from the first memory space into the second memory space leaving the unreachable objects in the first memory space and allocating new objects into the second memory space.