IBM OS/390 User Manual
10.3.3.2 Serializing Job Execution
JES2 does not guarantee that jobs will run in the order they are submitted. If you
need to make certain jobs run in order or you need dependent job control, you
should submit them one at a time or use an automated job scheduling product
such as OPC/A.
need to make certain jobs run in order or you need dependent job control, you
should submit them one at a time or use an automated job scheduling product
such as OPC/A.
10.3.3.3 Time Event Scheduling
POWER supports the scheduling of job submission based on a one-time or
repetitive schedule such as daily, weekly on a given day and time, and so on.
repetitive schedule such as daily, weekly on a given day and time, and so on.
JES2 has a primitive
automatic command scheduling facility, but you will
probably need an automated scheduling package in OS/390 to do the same
thing.
thing.
10.3.3.4 Additional Job Scheduling Functions with MVS/JES2
The following functions are not available in VSE/POWER, but may be exploited in
OS/390 JES2:
OS/390 JES2:
Priority Aging When
′
Priority aging
′
is on, JES2 will periodically increase a jobs
priority for execution or printing, based on the length of time the job
has been in the queue. For example, JES2 can be instructed to
raise a job
has been in the queue. For example, JES2 can be instructed to
raise a job
′
s priority by 1 every hour that it
′
s been on the queue.
Time Limits A job
′
s priority can be based upon its estimated elapsed time which
can be specified on JECL statement or through JES2 exits. See the
JOBPRTY JES2 initialization statement. (The installation can choose
to cancel jobs exceeding their estimated time through initialization
parameters or exits.)
JOBPRTY JES2 initialization statement. (The installation can choose
to cancel jobs exceeding their estimated time through initialization
parameters or exits.)
The CPU time of a job can also be specified on the JOB or EXEC
JCL statement, and controlled by SMF exits.
JCL statement, and controlled by SMF exits.
Output Limits The output priority can be based upon its actual output size
according to the OUTPRTY JES2 initialization statement.
Job limits are based on JES2 estimated counts, JECL statements
and JES2 exits, and can be extended or controlled by JES2 Exit 9.
and JES2 exits, and can be extended or controlled by JES2 Exit 9.
Data set limits are based on the OUTLIM parameter of the DD
statement. They can be extended or controlled by the IEFUSO SMF
exit.
statement. They can be extended or controlled by the IEFUSO SMF
exit.
JCL Conversion This happens much earlier in the job
′
s processing in OS/390
than in VSE. JECL (JES2 control cards) are processed at reader
time. JCL is converted soon after reader time, then interpreted
during step initialization.
time. JCL is converted soon after reader time, then interpreted
during step initialization.
Resource Affinity With OS/390 Version 2 Release 4, jobs can be selected
according to the scheduling environment specified on the JOB card,
and based on the availability or abstract resources as controlled by
the workload manager.
and based on the availability or abstract resources as controlled by
the workload manager.
Workload Managed Batch Initiators With OS/390 Rel.4, jobs can be selected
based on installation defined performance objectives when running
in
in
″
Goal
″
mode.
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VSE to OS/390 Migration Workbook