Excessive CPU in GSS address space

Products

• Bind Analyzer for DB2 for z/OS
• SQL-Ease for DB2 for z/OS
• SYSVIEW Performance Management Option for DB2 for z/OS
• Plan Analyzer for DB2 for z/OS
• Subsystem Analyzer for DB2 for z/OS
• Database Management for DB2 for z/OS - Performance Suite
• Database Management for DB2 for z/OS - SQL Performance Suite

Issue/Introduction

Increase in CPU in GSS address interfacing with IDB2.

IDB2MEXC IMOD System Condition Monitor.

Environment

Release : 20.0

Component : CA Insight Database Performance Monitor for DB for z/OS

Cause

The high CPU was in the IDB2MEXC IMOD.  This IMOD adds exceptions to the System Condition Monitor.  The SCM main screen's "Exception Count" column for the subsystem revealed an extremely high number count for the RBNDRQRD exception.  This was the cause of the High CPU in the IDB2MEXC IMOD in the GSS Address space.

Resolution

Turning off the RBNDRQRD exception in IDB2's Exception Processor, and then recycling the Exception processor alleviated the high CPU in GSS.

Additional Information

A circumvention to disabling the RBNDRQRD exception would be to comment out the line:

'SCM-IMOD-NAME=IDB2MEXC' from the IDB2 SYSPARMS.  This will disable calls to this IMOD.