Controlling levels of system activity

Controlling levels of system activity

You can control how much activity is on the system by controlling how many jobs can be active at the same time in a subsystem or by controlling the use of the processing unit by jobs that have already been started.

Table 1. Ways to control system activity levels
What can I control? What can I use to control? Character-based interface method iSeries™ Navigator interface method

Number of active jobs Subsystem Description Command: CHGSBSD MAXJOBS
Use this parameter to specify how many jobs can be active at the same time in a subsystem.
For an active subsystem, the sum of all of the jobs that are active at the same time that are started through work entries in the subsystem cannot exceed the MAXJOBS parameter value.
This excludes autostart jobs, which might temporarily cause the limit to be exceeded when the subsystem is started.
Use the Run Command window.
Right-click the endpoint system > Run Command
Type the command CHGSBSD and then click Prompt.
Job Queue Entry Command: CHGJOBQE MAXACT
Use this parameter to specify how many batch jobs from a job queue can be active at the same time in the subsystem.
A MAXACT of 1 for a job queue forces jobs to be selected serially by job priority from a job queue. The MAXPTYn parameter is used to specify how many jobs can be active for a specified job priority.
Use the Run Command window.
Right-click the endpoint system > Run Command
Type the command CHGJOBQE and then click Prompt.
Workstation Entry Command: CHGWSE MAXACT
Use this parameter if the WRKSTNTYPE parameter is specified. This parameter specifies how many interactive jobs can be active at the same time in the subsystem for that entry.
Use the Run Command window.
Right-click the endpoint system > Run Command
Type the command CHGWSE and then click Prompt.
Communications Entry Command: CHGCMNE MAXACT
Use this parameter to specify how many communications batch jobs can be active at the same time for that entry.
Use the Run Command window.
Right-click the endpoint system > Run Command
Type the command CHGCMNE and then click Prompt.
Routing Entry Command: CHGRTGE MAXACT
Use this command to specify how many jobs can be active at the same time using a given routing entry.
Use the Run Command window.
Right-click the endpoint system > Run Command
Type the command CHGRTGE and then click Prompt.
Prestart job entry Command: CHGPJE MAXJOBS
Use this command to specify how many prestart jobs can be active at the same time for that entry.
Use the Run Command window.
Right-click the endpoint system > Run Command
Type the command CHGPJE and then click Prompt.
Number of active jobs (continued) System The Maximum eligible threads (QMAXACTLVL) system value is used to specify how many threads can share main storage and processor resources at the same time. All active jobs (including system jobs) in all storage pools are controlled by QMAXACTLVL.
My Connections > server > Configuration and Service > System Values > Performance category > Memory Pools tab > Maximum eligible threads
Use of processing unit and main storage Base storage pools The Base memory pool maximum eligible threads (QBASACTLVL) system value is used to specify how many threads can share the Base storage pool at the same time and to limit main storage contention.
My Connections > server > Configuration and Service > System Values > Performance category > Memory Pools tab > Base Memory pool: Maximum eligible threads
Shared pools Command: WRKSHRPOOL
Use this command to specify the activity level for shared pools

My Connections > server > Work Management > Memory Pools > Shared Pools > right-click a shared pool > Properties > Configuration tab and change the Maximum eligible threads field
Private storage pools Command: CHGSBSD POOLS
Use this command to specify the activity level for user-defined main storage pools.
Use the Run Command window.
Right-click the endpoint system > Run Command
Type the command CHGSBSD and then click Prompt.

Examples: activity control relationships
These examples show the relationship of some of the activity controls. Assume the system activity level is 100 and the jobs are single-threaded.

Parent topic:
Monitoring system activity