The system arbiters (QSYSARB and QSYSARB2 through QSYSARB5), started
by an SCPF system job, provide the environment for the running of high-priority
functions. They allow subsystems to start and end and keep track of the state
of the system (for example, a restricted state).
The system arbiters, identified by the job name QSYSARB and QSYSARB2 through
QSYSARB5, are the central and highest priority jobs within the operating system.
Each system arbiter responds to system-wide events that must be handled immediately
and those that can be handled more efficiently by a single job than multiple
jobs.
The system arbiter (QSYSARB) is also responsible for starting
the Logical Unit Services (QLUS) job during an IPL. The system arbiter remains
active until the system is ended.
The following is a list of system arbiters.
- Qsysarb (system arbiter)
- The system arbiter provides the environment for the running of high-priority
functions. It handles system resources and keeps track of the state of the
system. The system arbiter responds to system-wide events that must be handled
immediately and those that can be handled more efficiently by a single job.
Qsysarb, Qtaparb (tape arbiter), and Qcmnarbxx (communications arbiters)
are responsible for processing communication requests, device locking, line,
controller, and device configuration, and handling of other system-wide resources.
- Qsysarb2 (system arbiter 2)
- This job is responsible for managing tape resources, handling command
analyzer spaces for command processing and other system-wide processing for
the operating system.
- Qsysarb3 (system arbiter 3)
- This job is responsible for creating and maintaining the job structures
on the system. Whenever temporary or permanent job structures are required
for job initiation, the request is processed by Qsysarb3. Qsysarb3 also starts
and ends many of the system jobs.
- Qsysarb4 (system arbiter 4)
- This job is responsible for starting and ending subsystems. This includes
the initial power down (Pwrdwnsys) processing.
- Qsysarb5 (system arbiter 5)
- This job is responsible for processing machine events. This includes handling
events to support auxiliary power, system auxiliary storage pools (ASPs) and
storage threshold, and lock table limits. Usually, the machine events are
handled and corresponding CPF messages are sent to Qsysopr and Qhst.