TMF Glossary (G06.26+)
TMF Glossary
HP NonStop TMF Glossary—522415-003
Glossary-3
autoabort threshold
autoabort threshold. The time limit used to identify long-running transactions that should
be aborted. When a transaction runs longer than the threshold, TMF aborts it. To
change this threshold, use the ALTER BEGINTRANS command.
auxiliary audit trail. An audit trail configured in addition to the master audit trail. Auxiliary
audit trails receive the audit information generated by a specified set of audited
volumes; they do not contain TMF control information. Up to 15 auxiliary audit trails
may be added to a TMF configuration to increase overall auditing capacity and
bandwidth, or to logically separate operations related to sets of audited volumes.
Auxiliary audit trails are named AUXnn, where nn is a two-digit number from 01 to 15
(AUX01, for example).
availability. The amount of time an application running on a NonStop system can be used
effectively by a user of that application.
B
backout. To remove all the database changes performed by a transaction that was aborted.
backup. See online backup, offline backup, and audit dump.
before-image. A copy or copied portion of a database record made before a transaction
changes it. Before-images are used in backing out aborted transactions.
begin-transaction-disable threshold. A configurable parameter (of the audit trail) that
specifies, as a percentage of overall audit trail capacity, the point at which TMF
prevents new transactions from starting.
begin-transaction object. A TMF object that affects the ability of new transactions to start
when applications call the BEGINTRANSACTION procedure. In normal system
operation, BEGINTRANSACTION is enabled. When a system condition causes
BEGINTRANSACTION to become disabled, new transactions cannot start.
big file. See format 2.
blocksize. The tape data block length, in bytes, when multiplied by 1024; the default is 28.
C
cache. Memory into which data is read, retained, and perhaps updated before being written
to disk, for more efficient processing.
catalog. See TMF catalog.
checkpoint. On a NonStop system, a status report of process activity that can be used in
the event of a takeover to allow a backup process to maintain fault-tolerant operation.