Main memory comprises resident pages and pages which are managed in working sets and in the free pool, see section “Page management algorithm” in chapter section "Page management algorithm".
A working set contains virtual pages which can be currently accessed but which can be relocated to paging memory.
The free pool comprises pages whose contents are either no longer needed or - at least temporarily - are to be stored in the paging memory. The free pool is filled from the working sets as required.
Main memory > 2 GB is supported in BS2000 native mode for the VM2000 monitor system and for each VM2000 guest system.
Command | Meaning |
ADD-USER | Define the number of resident main memory pages for the user programs of an ID (RESIDENT-PAGES) |
MODIFY-MEMORY-PARAMETERS | Define the percentage of main memory which is used for big page memory and whether and when big page memory may be reduced or enhanced |
MODIFY-SYSTEM-BIAS | Define the number of resident main memory pages for user programs |
MODIFY-USER-ATTRIBUTES | Change the number of resident main memory pages for the user programs of an ID (RESIDENT-PAGES) |
SHOW-MEMORY-CONFIGURATION | Display the current configuration of main memory including details of big page memory |
SHOW-SYSTEM-STATUS | Display the number of resident main memory pages for user programs (INFORMATION=SYSTEM-PARAM) |
SHOW-USER-ATTRIBUTES | Display the number of resident main memory pages for the user programs of an ID (RESIDENT-PAGES) |
Table 7: Overview of main memory management commands