PR/SM, short for Processor Resource Manager/System Manager, is a feature provided by IBM System/390 mainframes, which allows multiple logical partitions (LPARs) on a single physical system. Each LPAR can run different operating systems and applications, with dedicated or shared resources, including storage and CPUs.
PR/SM works in tandem with VM, another IBM operating system that provides software-based virtualization, enabling PR/SM to offer several system images in software. Both PR/SM and VM help deliver efficient resource management, improving system performance and utilization.
The functionality of PR/SM extends to channel sharing as well, which means that ESCON and FICON channels can be shared between the various images on the system through a mechanism called MIF (Multi-Image Facility).
What is an LPAR?
LPAR stands for Logical Partition. It is a virtualized server created by dividing a physical computer into multiple logical divisions, each running its own operating system and applications.
How does PR/SM differ from VM?
While both PR/SM and VM offer virtualization capabilities and help with resource management, they differ in terms of how they achieve it. PR/SM provides virtualization at the hardware level, while VM does it at the software level.
With PR/SM and VM, IBM provides powerful tools to enable efficient systems management for mainframes, helping organizations to get the most out of their hardware resources.