VARKON Version 1.16 1999-02-11

### PMSIZE

System variable

Description

PMSIZE is the size of the PM memory area in bytes. Default value = 400Kb. PMSIZE can be increased (or decreased) by supplying the -pm parameter on the commandline when VARKON is started.

Example:

-pm800000

Sets PMSIZE = 0.8Mb

PM is the place where VARKON keeps the active module and PMSIZE therefore sets the maximum size of the active module. VARKON also allocates a second memory area of the same size as PM and uses this to keep modules that are called by the active module. Subsequently PMSIZE also sets the maximum size of a called module.

The secondary PM is used as a cache. When a module is called for the first time it is always loaded from disc but when it is executed it is left in the cache. If the module is called again and hasn't left the cache it does not need to be read from disc a second time. This process goes on until the cache is full of modules and there is no room for another module. When this happens the entire cache is cleared and the process is started from the beginning again.

Comments

The cache mechanism of the secondary PM can increase execution speed significantly if PMSIZE is large enough to hold all called modules at the same time.

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