Permanent Lifetimes Global variables and constants. Allows fixed address to be compiled into code. No runtime management costs.
Most architectures support cheap sp -based addressing.
Good locality for VM systems, caches. Lisp, ML, many interpreted languages need heap for activation records, which have non-nested lifetimes. Procedures and Activations A procedure definition associates a name with a procedure body and associated formal parameters . Procedure f is recursive if two or more activations of f are nested . Execution corresponds to depth-first traversal of tree.