IBM 000-8697 用户手册
Product Environment
9-35
Heuristic Decisions: What and Why
Figure 9-9
Characteristics of Heuristic “End-Transaction”
When it occurs
:
A heuristic end-transaction occurs after the participant
OnLine sends a “can commit” message for a piece of
work.
OnLine sends a “can commit” message for a piece of
work.
Why it occurs:
Administrator executed.
tbmode -Z
tbmode -Z
address, terminating the piece of work being
performed on behalf of the global transaction.
What occurs:
This piece of work is rolled back and ended at this
OnLine database server, independent of coordinator
instructions.
OnLine database server, independent of coordinator
instructions.
Shared memory:
Shared-memory resources are released. Transaction
entry is removed from the transaction table.
entry is removed from the transaction table.
Logical log files:
All records associated with the piece of work are closed.
Files containing these records can be freed, if all other
conditions are met.
Files containing these records can be freed, if all other
conditions are met.
Logical log:
ENDTRANS
logical log record is written.
ROLLWORK
log
record is written if it does not already exist.
Coordinator:
The lack of a transaction entry in shared memory is
interpreted by the coordinator to mean that the piece of
work has committed.
interpreted by the coordinator to mean that the piece of
work has committed.
OnLine messages:
“Transaction completed abnormally (endtx)” is written
in the participant OnLine message log.
in the participant OnLine message log.