Hands-on scenario: Solving a z/OS performance problem
You can use the System Health dashboard to quickly identify
problems in your mainframe environment, navigating from a filtered list of performance or automation
events to detailed performance data or automation status to help you to isolate issues
faster.
About this task
In this best practice, you will identify, isolate and resolve real problems in a z/OS® environment using Service Management Unite. Firstly, you detect z/OS performance problems (such as high CPU and an excessive wait for an enqueue) and analyze the situation. Next, you learn how to cancel address spaces to restore service again.
Hands-on video:
You can watch this video and follow the guide to perform actions in the video at the same time.
Click here (https://ibm.biz/BdYAUV) to watch the video in full screen.
Procedure
On the Welcome page, select Monitor System Health
dashboard.
The Monitor System Health page is displayed. Note that component z/OS shows critical events on the left hand side.
In the Health Status widget, select the z/OS component to only display the events related to z/OS in the Events widget.
Right click one of the error events. In the drop-down menu, select View LPAR
Details.
The LPAR Details page opens showing key performance and status data for this z/OS LPAR.
The Enqueue and Reserve Summary widget displays information about all
global enqueue conflicts and reserves for the system. Right click on the displayed entry and select
Isolate Problem.
The problem isolation page opens. It shows detailed information about the selected enqueue
conflict. In the Enqueue and Reserve Details widget, you can see the address
space that owns the resource, and the address space that is waiting for it. The Wait Time
shows how long the task of the waiting address space has been waiting for the
resource.
Maximize the Suggested Actions widget on the page using the widget
menu.
The Suggested Actions widget lists typical problems and suggested
solutions. One recommended action is to cancel the job that holds the ENQ.
Switch back to the LPAR Details page.
On the LPAR Details page, right click again on the ENQ job listed in the
Top 5 CPU Uitlization widget. The drop-down menu provides access to common
commands.
Select Cancel ENQ Address Space. The Issue
Command page opens with the Cancel command pre-filled.
MVS CANCEL ENQ,A=00BF
Click Go on the Issue Command page.
Switch back to LPAR Details page. Refresh Top 5 CPU
Uitlization , Address Space Bottleneck and
Enqueue widgets.
The job ENQ no longer exists in the table.
Repeat step 7 to 8 to cancel ENQ2 as well, which takes over as CPU hog.
Results
The address spaces with excessive CPU usage is canceled, and the service is
restored.