Zowe and managing z/OSMF spawned tasks (IZUPROC)

Products

• Zowe

Issue/Introduction

A user experienced high utilization caused by numerous TSO address spaces running due to Zowe usage,
spawned by z/OSMF proc IZUPROC.

Is it possible to tweak the priority level of TSO address spaces spawned by z/OSMF proc, IZUPROC?
Is there any guidance on determining an optimal number for the MAXTHREADS parameter allowed in OMVS?

Environment

Zowe and z/OSMF proc IZUPROC

Resolution

There is no feature within Zowe to throttle API requests. Consider the following:

1. The dispatching priority for z/OSMF TSO regions under IZUPROC is determined by WLM assignments.
   In goal mode WLM, the PRTY= value in the logon procedure is effectively ignored.
   In order to adjust the priority, classify address spaces into desired service classes.
   Sites can accomplish this by using WLM attributes
        1.  Logon procedure (IZUPROC)      
        2.  User ID prefix (IZU*)      
        3.  Account number supplied by the proc   
   
   Once separated into their own service class, adjust the period goals and importance levels and
   this will accordingly modify the dispatching priority.
   
   
2. Adjust the MAXTHREADS parameter in OMVS configuration to an optimal number by monitoring
   and tuning based on specific workload and system performance.