Why is my Datacom job connecting to MUF via XCF even if running on the same LPAR?

Products

• Datacom
• DATACOM - AD
• CIS
• COMMON SERVICES FOR Z/OS
• 90S SERVICES
• DATABASE MANAGEMENT SOLUTIONS FOR DB2 FOR Z/OS
• COMMON PRODUCT SERVICES COMPONENT
• Common Services
• CA ECOMETER SERVER COMPONENT FOC
• Easytrieve Report Generator for Common Services
• INFOCAI MAINTENANCE
• IPC
• UNICENTER JCLCHECK COMMON COMPONENT
• Mainframe VM Product Manager
• CHORUS SOFTWARE MANAGER
• CA ON DEMAND PORTAL
• CA Service Desk Manager - Unified Self Service
• PAM CLIENT FOR LINUX ON MAINFRAME
• MAINFRAME CONNECTOR FOR LINUX ON MAINFRAME
• GRAPHICAL MANAGEMENT INTERFACE
• WEB ADMINISTRATOR FOR TOP SECRET
• Xpertware

Issue/Introduction

A job (MYDBJOB1), executing a Datacom utility or a user application, runs on the same LPAR (SYS1) where the Datacom MUF is currently active but, based on the DB00133I  message:
DB00133I - JOB OPEN MYDBJOB1 15688 USER01 JOB12345 XCF-SYS1
the connection between the two address spaces occurs via XCF

Why does the connection between MYDBJOB1 and the Datacom Multiuser region occur in XCF mode and not locally?  

Environment

Release: DATABB00200-14.0-Datacom/AD
Component:

Resolution

DBSYSID macro has been assembled with: CONNECT_ALLOW_PRIORITY=(XCF,LOCAL) so XCF is the preferred connection method, even if the MUF and the job are running on the same LPAR.

DBSYSID must be changed to read:
CONNECT_ALLOW_PRIORITY=(LOCAL,XCF)
and then DBSIDPR must be reassembled and relinked .

Additional Information

XCF is an added overhead and less efficient than LOCAL connection when both the job and the MUF are running on the same LPAR.