- VLF keeps objects (for example Load modules) in Virtual Storage in order to save I/O operations that would load such objects.
- Designed primarily to improve performance by retrieving the most currently used objects from Virtual Storage rather then performing repetitive I/O operations from DASD.
- VLF can be configured by using PARMLIB member COFVLFxx.
Examples of some VLF exploiters:
- LLA (for Load modules)
- TSO (for REXX and CLIST procedures)
- CAS – Catalog Address Spaces (for User Catalog entries)
- RACF records from its database