IDUG NA 2025

Distributed client applications (from a server) are the most important and common of new workload using Db2 Z.  
There are many concepts and terms thrown around which we often too often gloss over without a complete understanding.
This presentation will re–explain basic terms from my user perspective plus share some experiences learned (the hard way?) over recent years.
 
This presentation covers THREADS and DBATS and CONNECTION.   
Db2 command DISPLAY DDF DETAIL will show valuable information about current DBAT usage (in–use and disconnected).  
Db2 command DISPLAY THREAD LOCATION(*) will show information about all the in–use DBAT (active, disconnecting or connecting).
Db2 itself monitors current in–use DBATS and spits out interesting message DSNL077I when in–use DBAT reaches 85% of MAXDBAT.  This is an important clue that something is probably going wrong!
Db2 statistics tell us all the same meta data about DBAT info.  Reviewing Db2 statistics, via a good Db2 performance database, can provide reports and trends on DBAT usage over time along with CPU consumption by DDF
The presentation will end with my user experience of an application issue of hitting max in–use DBAT and understanding what was going on!