Multiple event with same schedule cause duplicate Application Generation

Products

• CA Workload Automation DE - Scheduler (dSeries)
• CA Workload Automation DE

Issue/Introduction

In some rare cases, an application with multiple events and same schedule may cause application generation to overwrite.

Environment

Release : 12.3

Component : CA WORKLOAD AUTOMATION DE (DSERIES)

Cause

As of R12 ESP dSeries (DE), the event engine is multithreaded.  The DE sever, by default, can trigger 10 events concurrently.   If an application has multiple events that trigger at the same time, then in some cases application generation in database may get overwritten.  

E.g 

If an application APPL123 is started twice by two different events at the same time, then both events will try to get a generation number.  The DE database stores highest generation number for each application.  Each time an event is triggered, the DB table is read to determine new generation number (current +1).  In a very rare case two events may read the same application generation and will try to update the same generation number.  

The generation number may get incremented or even rolled back.  This can result any future generation to have same number as before and previous application generation data may get overwritten.

Resolution

To prevent the duplicate generation, stagger the events by a minute.  The events will then not read and/or update the database table simultaneously.