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HELP POPMEMLIM A. Law, August 1987 The variable -popmemlim- has an integer value that specifies the maximum number of words to which the system should expand the combined memory area for the heap and user stack. The related variable -popminmemlim- is used to specify the minimum allocation of space. It is often useful if you need to force the memory manager to make use of available memory. See REF * POPMINMEMLIM If attempting to create a data-structure proves impossible because all the space in the heap is in use, the store manager will cause a garbage collection. If there is still not enough space it will try to allocate extra space, within the limit set by -popmemlim-. If there is already that amount of heap+stack space allocated, and there is no space to create a data-structure required y the user, then system will mishap, with the message: ROM: MEMORY LIMIT (popmemlim) EXCEEDED (allocating XXX space) where XXX is 'heap' or 'stack' to indicate whether the memory allocation request that caused the mishap was for a data structure in the heap, or for space on the user stack. The default value for -popmemlim- is 100000 (i.e. 400,000 Kbytes) (but higher defaults are used by the Prolog and Lisp systems); if this is not large enough for your program, you should experiment with increasing it gradually (e.g. in steps of 100000, or doubling it, etc). (Increasing it by too large an amount may cause garbage collections to become slower, by virtue of there being insufficient extra memory available to use the copying GC algorithm -- see REF * SYSTEM). Note that, regardless of POPMEMLIM, the mishap 'ROM: NO MORE MEMORY AVAILABLE (allocating XXX space)' may also occur; this indicates that the system can expand no further, because no more memory can be allocated from the operating system (either because of a set limit on process size, or through a lack of swap space, etc). -- RELATED DOCUMENTATION ---------------------------------------------- REF *SYSTEM - more details of system control procedures REF *PROCEDURE - (-pop_callstack_lim-) max length of call stack REF *PROLOG - (-pop_prolog_lim-) max size of continuation stack and trail --- C.all/help/popmemlim --- Copyright University of Sussex 1990. All rights reserved. ----------