Update SYSVIEW information via SYSTEMS command

Products

• SYSVIEW Performance Management

Issue/Introduction

The SYSTEMS command isn't updating the CP column values ​​when pressing ENTER.
It only updates at the minute. Also using the UPDATE 30 command, the update only happens at the minute.

What need to be changed?

Environment

SYSVIEW 17.0 - z/OS supported releases - 

Resolution

The data rows on SYSTEMS (the bottom half of the screen showing one row per system) displays data that was collected by the MVSDATA subtask on each system. This data is only updated once per minute by the collector, which matches the reported behaviour. This cannot be changed.

The top half of the screen is the OVERVIEW section, which can be shown on any SYSVIEW display by doing SET OVERVIEW ON. The cpu-related values shown in OVERVIEW can be either REALTIME (data is gathered realtime when you hit Enter key) or INTERVAL (data from MVSDATA collector, updated once per minute same as in the data rows below). This can be controlled using SET OVERVIEWTYPE REALTIME | INTERVAL.
The '(r)' in the upper left of the screen, indicates OVERVIEWTYPE is set to REALTIME. An (i) would indicate INTERVAL.

There are entries on SCHEDULE command that control how often the data collectors perform collection. The MVS-CPU entry controls cpu collection. The default is every 1 minute, but it can be lowered to a minimum of 10 seconds. So in theory the collection could be speed up. This would increase the monitoring overhead involved in doing that collection (changing from every 60 seconds to every 10 seconds increases overhead sixfold).

Even if the collection was more often than once a minute, the value seen on SYSTEMS is still going to be the average for the last two minutes. There would be more samples being taken over those two minutes.