Calculating priority

When a /*PRIORITY or PRTY= on the JOB statement do not specify the scheduling priority, JES2 calculates the priority from the estimatedexecution time. Supply these estimates through the: /*JOBPARM statement, the accounting information on the JOB statement, or the ESTIME initialization statement.

To calculate priority, JES2 uses the PRIORITY= and TIME= parameters on the JOBPRTY(n) initialization statement as a table of values. You can supply these values on the JOBPRTY(n) statement or allow them to default. The following example uses the default values to calculate priority:

Table 1. Priority Table Example
If TIME<=*	Then JOBPRTY(n)=	Then PRIORITY=**
2	(1)	9
5	(2)	8
15	(3)	7
279620	(4)	6
.	.	.
.	.	.
.	.	.
279620	(8)	2
279620	(9)	1

* The TIME values are estimates of the number of minutes a job requires to execute. ** These are the defaults for corresponding n values. For example, if you specify TIME= to estimate 4 minutes execution time, `4 minutes implies n=2 and n=2 implies PRIORITY=8`

If the job is placed on the HARDCOPY queue, JES2 ignores the job priority (for example, 8, as calculated in the above example); the actual priority used (in this example) is the output priority.

By specifying other values for the tables (during JES2 initialization), you can more closely control your installation's priority assignments. If you build your own priority table based on estimated execution time, be certain the values that you supply appear in ascending order (as are the values in the default table in Table 1). The order is important because JES2 uses the TIME= values in a “less than or equal to” order when calculating a priority that does not exactly match the values in the table.

For example, in Table 1, if you submitted a job with an execution time of 10, JES2 calculates n as 3 because 10 is less than or equal to 15. If the estimated execution time is 16 to 279620, n is 4. You can use n values 4 through 9 to further control you installation's priority requirements.

Note: Values specified on the JCL /*JOBPARM statement override those in the accounting field of the JOB statement.

During JES2 initialization, you can specify the ACCTFLD parameter on the JOBDEF initialization statement and cause JES2 to ignore the accounting field on the JOB statement.