Datacom hangs with many tasks in TASK ACTIVE status

Products

• Datacom

Issue/Introduction

The Datacom Multi-User facility ( MUF) seems to have stopped processing tasks.

A COMM STATUS report shows all tasks are waiting on other tasks which are all in TASK ACTIVE status.

Environment

z/OS

Datacom/DB 15.1

Cause

In this case , the Tasks that are in TASK ACTIVE status are active tasks running in CICS.

See the documentation on COMM STATUS: 

TASK ACTIVE
The CICS transaction has a locked thread but is not currently waiting on a MUF request.

This means the Datacom tasks are waiting on CICS tasks to complete.

This does not indicate a problem in Datacom.

Resolution

Check the status of the active tasks in CICS and take the appropriate action. Use CEMT I TASK or some other CICS monitor.

Information about the CICS task Datacom is waiting on is in the ID section of the COMMS STATUS display. For example:

DB01328I - TIME   I/O  JOBNAME R-UNIT TASK CMD-DBID-TBL    SEQ STATUS          ID               TSN
DB01329I -             PCICS   99502  221 ADDIT 100ASE        TASK ACTIVE     R112D084XXX30480 0C25A76D

The ID is R112D084XXX30480 this consists of:

• First 4 bytes is the transaction ID = R112
• Next 4 bytes is the terminal ID = D084
• Next 3 bytes is the operator ID = XXX
• Next 5 bytes is the task identification number = 30480

In this case , issue in CICS -  CEMT I TASK(30480)