What is the criteria used by OPS/MVS to start a new OSF server?

Products

• OPS/MVS Event Management & Automation

Issue/Introduction

What is the criteria used by OPS/MVS to start a new OSF server?

 

Environment

OPS/MVS 
 

Resolution

The algorithm that is used to add servers depends on the OSFQADDPROCESS parameter.

If OSFQADDPROCESS=AVAIL a new server is added, when the number of commands in the OSF TSO execution queue is higher than OSFQADD and OSFMIN but lower than OSFMAX.

When OSFQADDPROCESS=QADD a new server is added when the queue depth equals OSFQADD+1 + (n * OSFQADD) until OSFMAX is reached. Where ‘n’ equals the number of dynamically added servers.

OSFQADDPROCESS=QADD is the default and recommended setting to optimize performance. The calculation results in a 'slower' rate of adding servers, so that the overhead of a task starting and stopping in the system is decreased. It also takes into account the fact that with a larger number of servers active, the chances are greater that work will end, in one of the servers, and it will be ready for/get work from the OSF queue, before another server can actually start and be fully initialized.