TMF Glossary (G06.24+)

TMF Glossary
HP NonStop TMF Glossary—522415-002
Glossary-18
transaction management process (TMP)
transaction management process (TMP). The TMF management process pair, always
named $TMP, coordinates transactions distributed over a network. The TMP is also in
charge of operations that require a single point of control in a system, such as starting
and stopping TMF, initiating recovery processes, and implementing configuration
changes. The TMP manages the data volumes and audit trails and is the final
authority on whether transactions are committed or aborted; it also creates other TMF
processes as needed.
transaction mode. The operating mode of a terminal program between the execution of a
BEGINTRANSACTION statement and the execution of the associated
ENDTRANSACTION or ABORTTRANSACTION statement.
transaction pseudofile (TFILE). A construct used by TMF to provide access control block
(ACB) space for transaction control and state information. The TFILE does not reside
on a physical I/O device.
two-phase commit. An industry-standard series of operations performed when an
ENDTRANSACTION statement is executed to commit a transaction. In the first phase,
the before-images and after-images for the transaction are written to the audit trail on
disk. In the second phase, locks held by the transaction are released.
U
undo-needed file. An audited file that contains changes that must be undone because of
one or more aborted transactions. Such files cannot be opened. They are automatically
recovered by the volume recovery process when that is possible; otherwise, you must
use the file recovery process to recover them.
unilateral abort. An abort caused by a participant in a transaction that is not yet in the
prepared state.
unresolved transaction. A distributed transaction that TMF cannot determine whether to
commit or abort. This transaction was in the prepared state when the communication
lines between the home and remote nodes failed, and remains in this state until either
the connection between the nodes is reestablished or the transaction is resolved by an
operator. Sometimes, unresolved transactions are also called in-doubt transactions.
user-defined transaction. A TMF transaction initiated by an application either in a program
unit or in a requester on whose behalf the program unit performs database operations.
Contrast with system-defined transaction.
V
volatile resource manager. A resource manager that represents data that does not need to
be recovered after a failure, such as objects in main memory, user processes
maintaining transactional variables, window managers, and servers maintaining
context during transaction execution.