How does Thread Terminator select threads to cancel that exceed thresholds in multiple termination profiles?

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
• Insight Performance Monitor for DB2 UDB for z/OS

Issue/Introduction

The Thread Terminator profile that is more generic is cancelling threads ahead of a more specific profile.

Environment

Release : 19.0

Component : Thread Terminator

Resolution

The thread monitor sorts the termination profiles from most specific to least specific during thread monitor startup. This sorting is unrelated to the sorting by column name that we see in the user interface.

 

When the “A=All matching” option is set, the thread monitor will use all matching termination profiles each time that it wakes up, starting with the most specific termination profile.  Therefore, we recommend specifying the highest thresholds in the least specific termination profiles when the “A=All matching” option is set.  
 
Setting the “B=Best matching only” option is the only way to prevent the thread monitor from using less specific termination profiles after using the most specific termination profile each time the thread monitor wakes up.