Intelligent Resource Director
Encyclopedia
On IBM mainframe
s running the z/OS
operating system
, Intelligent Resource Director (IRD) is software that automates the management of CPU resources and certain I/O
resources.
IRD is implemented as a collaboration between Workload Manager
(WLM), a component of z/OS, and the PR/SM
Logical Partitioning (LPAR
) hypervisor
, a function of the mainframe
hardware.
Major IRD functions are:
IRD's objective is to optimise the use of computing resources while enabling WLM to meet its workload goals. So, for example, IRD will not vary offline logical processors to the point where doing so would cause workloads to miss their goals.
IBM mainframe
IBM mainframes are large computer systems produced by IBM from 1952 to the present. During the 1960s and 1970s, the term mainframe computer was almost synonymous with IBM products due to their marketshare...
s running the z/OS
Z/OS
z/OS is a 64-bit operating system for mainframe computers, produced by IBM. It derives from and is the successor to OS/390, which in turn followed a string of MVS versions.Starting with earliest:*OS/VS2 Release 2 through Release 3.8...
operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
, Intelligent Resource Director (IRD) is software that automates the management of CPU resources and certain I/O
I/O
I/O may refer to:* Input/output, a system of communication for information processing systems* Input-output model, an economic model of flow prediction between sectors...
resources.
IRD is implemented as a collaboration between Workload Manager
Workload Manager
In IBM mainframes, Workload Manager is a base component of MVS/ESA mainframe operating system, and its successors up to and including z/OS. It controls the access to system resources for the work executing on z/OS based on administrator-defined goals. Workload Manager components also exist for...
(WLM), a component of z/OS, and the PR/SM
PR/SM
PR/SM is a type-1 Hypervisor that allows multiple logical partitions to share physical resources such as CPUs, I/O channels and direct access storage devices...
Logical Partitioning (LPAR
LPAR
A logical partition, commonly called an LPAR, is a subset of computer's hardware resources, virtualized as a separate computer. In effect, a physical machine can be partitioned into multiple logical partitions, each hosting a separate operating system....
) hypervisor
Hypervisor
In computing, a hypervisor, also called virtual machine manager , is one of many hardware virtualization techniques that allow multiple operating systems, termed guests, to run concurrently on a host computer. It is so named because it is conceptually one level higher than a supervisory program...
, a function of the mainframe
Mainframe computer
Mainframes are powerful computers used primarily by corporate and governmental organizations for critical applications, bulk data processing such as census, industry and consumer statistics, enterprise resource planning, and financial transaction processing.The term originally referred to the...
hardware.
Major IRD functions are:
- Logical CP Management - where IRD dynamically varies logical processors on- and off-line. (This does not apply to zIIPZIIPIn IBM System z9 mainframes, the System z Integrated Information Processor is a special purpose processor. It was initially introduced to relieve the general mainframe central processors of specific DB2 processing loads, but currently is used to offload other z/OS workloads as described below...
s or zAAPs.)
- Weight Management - where IRD dynamically redistributes LPAR weights between members of an LPAR Cluster. (An LPAR Cluster is the set of members of a Parallel SysplexIBM Parallel SysplexIn computing, a Parallel Sysplex is a cluster of IBM mainframes acting together as a single system image with z/OS. Used for disaster recovery, Parallel Sysplex combines data sharing and parallel computing to allow a cluster of up to 32 systems to share a workload for high performance and high...
on a single mainframeMainframe computerMainframes are powerful computers used primarily by corporate and governmental organizations for critical applications, bulk data processing such as census, industry and consumer statistics, enterprise resource planning, and financial transaction processing.The term originally referred to the...
footprint.) The total of the weights for the LPAR Cluster remains constant as weights are shifted between the members. (zLinux LPARs can also participate in Weight Management.)
- CHPID Management - where logical channel paths are moved between members of an LPAR Cluster.
IRD's objective is to optimise the use of computing resources while enabling WLM to meet its workload goals. So, for example, IRD will not vary offline logical processors to the point where doing so would cause workloads to miss their goals.