Managing the state of each unit of work – IBM SC34-7012-01 User Manual

Page 30

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Managing the state, and controlling the execution, of each UOW

v

Coordinating UOW-related changes during syncpoint processing for recoverable
resources

v

Coordinating UOW-related changes during restart processing for recoverable
resources

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Coordinating recoverable conversations to remote nodes

v

Temporarily suspending completion (shunting), and later resuming completion
(unshunting), of UOWs that cannot immediately complete commit or backout
processing because the required resources are unavailable, because of system,
communication, or media failure

Managing the state of each unit of work

The CICS recovery manager maintains, for each UOW in a CICS region, a record of
the changes of state that occur during its lifetime.

Typical events that cause state changes include:

v

Creation of the UOW, with a unique identifier

v

Premature termination of the UOW because of transaction failure

v

Receipt of a syncpoint request

v

Entry into the indoubt period during two-phase commit processing (see the
CICS Transaction Server for z/OS Glossary for a definition of two-phase commit)

TD

FC

FC/RLS

DB2

DBCTL

MQM

MRO

LU6.1

LU6.2

RDO

TS

LOG

Manager

Recovery

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Reso

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Figure 3. CICS recovery manager and resources it works with

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CICS TS for z/OS 4.1: Recovery and Restart Guide

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