Abstract: An interactive system for debugging programs in which a persistent data base system responds to update queries containing debugging information from a debugging information source and to read queries on the debugging information from an interactive interface. The interactive interface produces the read queries in response to inputs from users and formats the results of the read queries as required by the user. One source of inputs is a standard Web browser for which the interactive interface functions as a Web server. The system also includes a command channel by which the source of debugging information receives commands from the interactive interface. In one embodiment, the command channel is implemented in the data base. In a disclosed implementation, the source of debugging information provides memory debugging information. Also disclosed are techniques for using an automatic memory management system to reduce memory fragmentation and heap footprint size.

Abstract: A system for selective self-healing of memory errors comprises a processor coupled to a memory, where the memory stores instructions executable by the processor to store an error record for each memory management error detected during an execution of the application. The error record identifies an allocation location (e.g., a portion of a stack trace corresponding to the invocation of a memory allocation function such as malloc( )) of an object associated with the memory management error. The instructions are executable to use the error record to identify, during subsequent execution, memory operations performed on objects allocated from the allocation location, and to perform corresponding memory protection operations (e.g., operations to prevent re-occurrences of the memory errors) for the memory operations identified using the error record.

Abstract: A method and mechanism for managing dynamically allocated memory. Portions of memory which are available for allocation have additional information stored in association with each portion which indicates whether the portion has been previously identified as being prematurely freed. In addition, a checksum is stored with each portion of memory. In response to a request for deallocation of a portion of memory, the portion of memory is not deallocated if it is identified as having been prematurely freed. Otherwise, the a checksum is calculated for the portion and it is freed. In response to an allocation request, a candidate portion of memory is identified for allocation and a checksum is calculated for the candidate portion. If the calculated checksum does not match a checksum previously stored for the candidate portion, the portion is identified as having been prematurely freed and is not returned for allocation.

Abstract: A memory manager comprises a memory allocator and a garbage collector. The memory allocator is configured to allocate memory for objects within a heap on behalf of a process, generate a heap map comprising a plurality of heap map entries, wherein each heap map entry of the plurality of heap map entries includes an address of an object allocated within the heap, and provide the heap map to the garbage collector. The garbage collector is configured to generate a mark list identifying one or more objects within the heap using the heap map, wherein the addresses of the one or more objects correspond to data values specified within an address space of the process, and to free a given object previously allocated in the heap if the mark list indicates that an address of the given object does not correspond to a data value specified within the address space.

Abstract: An interactive system for debugging programs in which a persistent data base system responds to update queries containing debugging information from a debugging information source and to read queries on the debugging information from an interactive interface. The interactive interface produces the read queries in response to inputs from users and formats the results of the read queries as required by the user. One source of inputs is a standard Web browser for which the interactive interface functions as a Web server. The system also includes a command channel by which the source of debugging information receives commands from the interactive interface. In one embodiment, the command channel is implemented in the data base. In a disclosed implementation, the source of debugging information provides memory debugging information. Also disclosed are techniques for using an automatic memory management system to reduce memory fragmentation and heap footprint size.

Abstract: An interactive system for debugging programs in which a persistent data base system responds to update queries containing debugging information from a debugging information source and to read queries on the debugging information from an interactive interface. The interactive interface produces the read queries in response to inputs from users and formats the results of the read queries as required by the user. One source of inputs is a standard Web browser for which the interactive interface functions as a Web server. The system also includes a command channel by which the source of debugging information receives commands from the interactive interface. In one embodiment, the command channel is implemented in the data base. In a disclosed implementation, the source of debugging information provides memory debugging information. Also disclosed are techniques for using an automatic memory management system to reduce memory fragmentation and heap footprint size.

Abstract: A technique that permits a conservative garbage collector to be used with the heap management functions provided by an allocator which is independent of the garbage collector. The allocator and the garbage collector (139) employ a malloc table (319) to exchange information about the heap (125). When the allocator determines that determines that garbage collection is required, the allocator makes a current heap map in the malloc table that specifies the location of each block in the current heap and whether the block is collectible by the garbage collector. The allocator then invokes the garbage collector, which uses the current heap map in its mark cycle to make a mark list that indicates which of the heap blocks are pointed to by apparent pointers in the processer's address space.

Abstract: An incremental garbage collector which permits a memory allocator's decommit mechanism to operate while the garbage collector is detecting memory that a program being executed is certainly not using. The garbage collector includes a decommit barrier which prevents the garbage collector from referencing memory that the allocator has decommitted from the address space of the process on which the program is executing. In mark-sweep incremental garbage collectors, the decommit barrier may be implemented in two ways: by means of a table which the allocator marks whenever it determines that a portion of memory is subject to being decommitted from the process's address space and which the garbage collector examines before scanning the portion and by means of a table which the garbage collector marks when it finds that a portion of memory must be scanned and which the allocator examines before decommitting the portion.