Performance system values: Dynamically adjust job priorities within priority bands

Sets job priorities within priority bands to be dynamically adjusted. (QDYNPTYSCD)

Dynamically adjust job priorities within priority bands, also known as QDYNPTYSCD, is a member of the performance category of i5/OS™ system values. You can use this system value to set the job priorities within priority bands to be dynamically adjusted. To learn more, keep reading.

Quick reference
Location In iSeries™ Navigator, select your system, > Configuration and Service > System Values > Performance > General
Special authority All object (*ALLOBJ) and security administrator (*SECADM)
Default value Selected - dynamically adjust job priorities within priority bands is turned on
Changes take effect At the next restart of the system
Lockable No

What can I do with this system value?

This system value allows you to turn on (1) and turn off (0) the dynamic priority scheduler. The task scheduler uses this system value to determine the scheduling of jobs for the processor. When enabled, the dynamic priority scheduler will adjust job priorities within priority bands, depending on each job's use of system resources. This typically allows greater throughput on the system, but may slightly alter the priority relationship between jobs within a band. For example, priorities 10-16 are in Band 1, 17-22 are in Band 2, 23-35 are in Band 3, 36-46 are in Band 4, 47-51 are in Band 5 and 52-89 are in Band 6.

Regardless of the value assigned to this system value, any jobs that are given a priority of 0 through 9 are put in a high-priority band 0. This band is always checked first by the task dispatcher before any other dynamic priority bands are checked. If a job in this band becomes processor bound (by looping), the job can lock the system.

Where can I get more information about this system value?

To learn more, go to the performance system values overview topic. If you are looking for a specific system value or category of system values, try using the i5/OS system value finder.

Related concepts
System values: Performance overview
Related information
System value finder