The class (CLS) parameter identifies the attributes that define
the run time environment of a job.
The following attributes are defined in each class:
- Run priority: A number that specifies the priority level assigned to all
jobs running that use the class. The priority level is used to determine which
job, of all the jobs competing for system resources, is run next. The value
can be 1 through 99, where 1 is the highest priority (all jobs having a 1
priority are run first).
- Time slice: The maximum amount of processor time that the system allows
the job to run when it is allowed to begin. The time slice indicates the amount
of time needed for the job to accomplish a meaningful amount of work (the
time used by the system for reading auxiliary storage is not charged against
the time slice). When the time slice ends, the job waits while other queued
jobs of the same or higher priority are allowed to run (up to the time specified
in their time slices); then the job is given another time slice.
- Purge value: Indicates whether the job step is eligible to be moved from
main storage to auxiliary storage while the job is waiting for some resource
before it can continue, or when its time slice is used up and equal or higher
priority jobs are waiting.
- Default wait time: The default amount of time that the system waits for
the completion of an instruction that performs a wait. This wait time applies
to times when an instruction is waiting for a system action, not to the time
an instruction is waiting for a response from a user. Normally, this would
be the amount of time you are willing to wait for the system before ending
the request. If the wait time is exceeded, an error message is passed to the
job. This default wait time applies only when a wait time is not specified
in the CL command that causes the wait.
The wait time used for allocating
file resources is specified in the file description and can be overridden
by an override command. It specifies that the wait time specified in the class
object is used. If file resources are not available when the file is opened,
the system waits for them until the wait time ends.
Note: The class attributes
apply to each routing step of a job. Most jobs have only one routing step,
but if the job is rerouted (because of something like the Remote
Job or Transfer Job command) the
class attributes will be reset.
- Maximum CPU time: The maximum amount of processor time (the sum of the
time slices if they differ, or time slice period multiplied by number of time
slices if they are equal) allowed for a job's routing step to complete processing.
If the job's routing step is not completed in this amount of time, it is ended,
and a message is written to the job log.
- Maximum temporary storage: The maximum amount of temporary storage that
can be used by a job's routing step. This temporary storage is used for the
programs that run in the job, for the system objects used to support the job,
and for temporary objects created by the job.
The system is shipped with a set of classes that define the attributes
for several job processing environments. Other classes can be created by the Create
Class (CRTCLS) command; any class can be displayed or deleted by
the respective Display Class (DSPCLS) and Delete
Class (DLTCLS) commands.
Values allowed
- qualified-class-name
- Specify the name of the class, optionally qualified by the name of the
library in which the class is stored. If the class name is not qualified and
the CLS parameter is in the CRTCLS command, the class object is stored in
*CURLIB; otherwise, the library list (*LIBL) is used to find the class name.
Classes
The following classes (by name) are supplied
with the system:
- QGPL/QBATCH
- For use by batch jobs
- QSYS/QCTL
- For use by the controlling subsystem
- QGPL/QINTER
- For use by interactive jobs
- QGPL/QPGMR
- For use by the programming subsystem
- QGPL/QSPL
- For use by the spooling subsystem printer writer
- QGPL/QSPL2
- For general spooling use in the base system pool