Working set size reduction by restructuring APL workspaces

Abstract

APL Workspaces usually have a random distribution of the defined APL functions. The physical location of a defined APL function within an APL workspace depends on its history of creation~ modification~ or copying. Furthermore in APL a good programming style results in a large number of small functions. The execution of an APL program in a virtual storage environment usually leads to comparatively large working set sizes because the APL functions are scattered over the workspace. However~ the interrelation between the functions can be analysed and exploited to reorganize a workspace and thus reduce the working set sizes. Methods of restructuring an APL workspace are proposed. Results of an investigation on a large APL/CMS workspace using these methods are presented. (2) Hatfield, D. J.: Experiments on Page Size~ Program Access Patterns~ and Virtual Memory Performance. IBM Journal of Research and Development 16, i~ 58-66~ 1972.