USER CONTROL OF MULTIPLE MEMORY HEAPS

The present invention provides the user with the ability to control and administer the supply of memory managed in multiple heaps by a library heap management facility. The control data used by the heap management facility is located in the user-supplied memory. Heaps are created dynamically through calls from the application to the runtime library. Allocation within a heap is performed through calls to the runtime library that canvass the available heap memory for each allocation request. If no suitable block of heap memory is located, additional user supplied memory is requested for the application through a callback function. A second callback function notifies the user when a supplied unit of memory is no longer required by the heap and may be disposed of. The callback functions are specified separately for each heap. The invention also provides the user with means for setting the default heap in the runtime library for use by allocation requests from a vendor library that do not specify a heap. This can be done on a per thread basis in multithreaded applications so that different executing threads can use different default heaps in a non-interfering manner.