Abstract: A method for creating an enhanced array is provided. An enhanced compiler generates an instrumented class file for an enhanced array class. The enhanced array class comprises at least one element class. The enhanced runtime loads the instrumented class file of the enhanced array class. The enhanced runtime loads a class file corresponding to the element class of the enhanced array class, and builds an internal data structure corresponding to the enhanced array class. An amount of memory storage is calculated for storing the enhanced array instance, and the amount of memory storage is allocated.

Abstract: A method for creating an enhanced array is provided. An enhanced compiler generates an instrumented class file for an enhanced array class. The enhanced array class comprises at least one element class. The enhanced runtime loads the instrumented class file of the enhanced array class. The enhanced runtime loads a class file corresponding to the element class of the enhanced array class, and builds an internal data structure corresponding to the enhanced array class. An amount of memory storage is calculated for storing the enhanced array instance, and the amount of memory storage is allocated.

Abstract: A method for creating an enhanced array is provided. An enhanced compiler generates an instrumented class file for an enhanced array class. The enhanced array class comprises at least one element class. The enhanced runtime loads the instrumented class file of the enhanced array class. The enhanced runtime loads a class file corresponding to the element class of the enhanced array class, and builds an internal data structure corresponding to the enhanced array class. An amount of memory storage is calculated for storing the enhanced array instance, and the amount of memory storage is allocated.

Abstract: A method for creating an enhanced array is provided. An enhanced compiler generates an instrumented class file for an enhanced array class. The enhanced array class comprises at least one element class. The enhanced runtime loads the instrumented class file of the enhanced array class. The enhanced runtime loads a class file corresponding to the element class of the enhanced array class, and builds an internal data structure corresponding to the enhanced array class. An amount of memory storage is calculated for storing the enhanced array instance, and the amount of memory storage is allocated.

Abstract: At least one region of a heap that includes memory allocations is analyzed, using age and occupancy criteria, across a number of local garbage collection cycles using a processor executing a region-based garbage collector. Based upon the analyzed age and occupancy criteria of the at least one region, at least one stable region in age and occupancy is identified among the at least one region of the heap across the number of local garbage collection cycles. Maintenance of a remembered set (RS) of external references into the at least one stable region is temporarily stopped for each identified stable region during at least one additional local garbage collection cycle.

Abstract: At least one region of a heap that includes memory allocations is analyzed, using age and occupancy criteria, across a number of local garbage collection cycles using a processor executing a region-based garbage collector. Based upon the analyzed age and occupancy criteria of the at least one region, at least one stable region in age and occupancy is identified among the at least one region of the heap across the number of local garbage collection cycles. Maintenance of a remembered set (RS) of external references into the at least one stable region is temporarily stopped for each identified stable region during at least one additional local garbage collection cycle.

Abstract: At least one region of a heap that includes memory allocations is analyzed, using age and occupancy criteria, across a number of local garbage collection cycles using a processor executing a region-based garbage collector. Based upon the analyzed age and occupancy criteria of the at least one region, at least one stable region in age and occupancy is identified among the at least one region of the heap across the number of local garbage collection cycles. Maintenance of a remembered set (RS) of external references into the at least one stable region is temporarily stopped for each identified stable region during at least one additional local garbage collection cycle.

Abstract: At least one region of a heap that includes memory allocations is analyzed, using age and occupancy criteria, across a number of local garbage collection cycles using a processor executing a region-based garbage collector. Based upon the analyzed age and occupancy criteria of the at least one region, at least one stable region in age and occupancy is identified among the at least one region of the heap across the number of local garbage collection cycles. Maintenance of a remembered set (RS) of external references into the at least one stable region is temporarily stopped for each identified stable region during at least one additional local garbage collection cycle.

Abstract: Tracking newly created objects during a garbage collection cycle includes marking newly allocated objects in the GC cycle during the allocation cache population phase. The goal is to take a high performance system for tracing live objects, such as the mark map, and combine the SATB with a cached allocation system for heap memory such that SATB representation is preserved. Embodiments combine both efficient support for an SATB model during a collection cycle and a highly optimized allocation path for heap objects in an allocation scheme (which may optionally be a size segregated class allocation scheme) that allows both mechanisms to co-exist effectively. Specifically, embodiments track newly created objects during a GC cycle such that they are kept alive during the trace phase while continuing to support a highly efficient allocating caching strategy.

Abstract: A method for efficiently implementing a remembered set for a region-based garbage collector includes maintaining, for each region in an object heap, a remembered set card list (RSCL). Each card in the RSCL identifies an area in the object heap that includes at least one object that references an object in the region associated with the RSCL. The method further establishes a collection set identifying a subset of regions in the object heap on which to perform partial garbage collection. Prior to performing the partial garbage collection, the method flushes cards from RSCLs associated with the collection set to the card table, globally discards cards that are about to be rebuilt from all RSCLs, and globally cleans the card table. The method then adds cards to the RSCLs for inter-region references discovered while traversing live objects in the collection set. A corresponding computer program product and apparatus are also disclosed.

Abstract: A method for performing garbage collection on an object heap is described. In one embodiment, such a method includes performing a copy phase on an object heap by copying live objects from a source space to a destination space. An abort condition is generated when copying an object from the source space to the destination space fails due to insufficient space. In response to the abort condition, tracing work and reference updating associated with the copy phase are terminated. A mark phase is then initiated that marks live objects in the source space. This mark phase resumes tracing work and reference updating terminated by the copy phase in order to avoid or minimize the repetition of work performed by the copy phase. A corresponding computer program product and system are also described.

Abstract: An illustrative embodiment of a computer-implemented process for single pass marking of finalizable objects marks strong roots, marks finalizable roots and determines whether a strong work stack is empty. Responsive to a determination the strong work stack is empty the computer-implemented process determines whether a finalizable work stack is empty. Responsive to a determination the finalizable work stack is empty, synchronize threads, the computer-implemented process finalizes finalizable roots and merges mark maps to finish parallel marking.

Abstract: An illustrative embodiment of a computer-implemented process for dynamic measurement and adaptation of a parallel copying garbage collector initializes values and data structures, receives an evacuate set, determines whether a new copy block is required and responsive to a determination that a new copy block is required, calculates a size of the new copy block. The computer-implemented process further selects a survivor region from a list of survivor regions to form a selected survivor region, places a lock on the selected survivor region, identifies a number of threads enqueued on the selected survivor region, responsive to a determination that a contention value exceeds a predetermined value, increases a size of the list of survivor regions, evacuates blocks to the selected survivor region and responsive to a determination that more evacuate blocks do not exist, terminates.

Abstract: A method for performing garbage collection on an object heap is described. In one embodiment, such a method includes performing a copy phase on an object heap by copying live objects from a source space to a destination space. An abort condition is generated when copying an object from the source space to the destination space fails due to insufficient space. In response to the abort condition, tracing work and reference updating associated with the copy phase are terminated. A mark phase is then initiated that marks live objects in the source space. This mark phase resumes tracing work and reference updating terminated by the copy phase in order to avoid or minimize the repetition of work performed by the copy phase. A corresponding computer program product and system are also described.

Abstract: An illustrative embodiment of a computer-implemented process for compaction planning selects a source region from a set of regions to form a selected source region, initializes process data using information from the selected source region and responsive to a determination that a current destination is not NULL and not full, determines whether to atomically consume from a destination. Responsive to a determination to atomically consume from a destination, the computer-implemented process plans to evacuate into a consumed extent and updates the process data and responsive to a determination that the source region is empty, determines whether more work remains. Responsive to a determination that more work does not remain, the computer-implemented process generates a relocation table.

Abstract: A method for incrementally unloading classes using a region-based garbage collector is described. In one embodiment, such a method includes maintaining a remembered set for a class set. The remembered set indicates whether instances of the class set are contained in one or more regions in memory, and in which regions the instances are contained. Upon performing an incremental garbage collection process for a subset of the regions in memory, the method examines the remembered set to determine whether the class set includes instances in regions outside of the subset. If the remembered set indicates that the class set includes instances outside of the subset of regions, the method identifies the class set as “live.” This will preclude unloading the class set from the subset of regions. A corresponding computer program product and apparatus are also disclosed herein.

Abstract: A method to implement parallel, single-pass compaction in a garbage collector is described. In one embodiment, such a method includes conducting a planning phase for multiple regions to be compacted. During the planning phase, the method determines new locations for data entities in the multiple regions. The method then performs a move phase for the multiple regions to move the data entities to their new locations. During the move phase, the method initiates multiple compaction threads to move the data entities to their new locations. While executing, the compaction threads dynamically build a dependency graph of the regions being compacted. The dependency graph guarantees that no data entity is moved to its new location until all data entities that it overwrites have been moved to their new locations. A corresponding computer program product and apparatus are also disclosed herein.

Abstract: A method to implement parallel, single-pass compaction in a garbage collector is described. In one embodiment, such a method includes conducting a planning phase for multiple regions to be compacted. During the planning phase, the method determines new locations for data entities in the multiple regions. The method then performs a move phase for the multiple regions to move the data entities to their new locations. During the move phase, the method initiates multiple compaction threads to move the data entities to their new locations. While executing, the compaction threads dynamically build a dependency graph of the regions being compacted. The dependency graph guarantees that no data entity is moved to its new location until all data entities that it overwrites have been moved to their new locations. A corresponding computer program product and apparatus are also disclosed and claimed herein.

Abstract: A method for incrementally unloading classes using a region-based garbage collector is described. In one embodiment, such a method includes maintaining a remembered set for a class set. The remembered set indicates whether instances of the class set are contained in one or more regions in memory, and in which regions the instances are contained. Upon performing an incremental garbage collection process for a subset of the regions in memory, the method examines the remembered set to determine whether the class set includes instances in regions outside of the subset. If the remembered set indicates that the class set includes instances outside of the subset of regions, the method identifies the class set as “live.” This will preclude unloading the class set from the subset of regions. A corresponding computer program product and apparatus are also disclosed herein.

Abstract: A runtime-resource management method, system, and product for managing resources available to application components in a portable device. The method, system, and product provide for loading one or more new application components into a portable device only if maximum runtime resources required by the one or more new application components are available in the portable device assuming loaded application components within the device are using the maximum runtime resources reserved by the loaded application components, reserving maximum runtime resources required by application components when application components are loaded into the portable device, and running loaded application components using only the runtime resources reserved for the loaded application components.