HP NonStop RDF, Руководство по управлению

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UPDATERTXTIME Attribute
The UPDATERTXTIME attribute specifies the maximum transaction duration in seconds (from
10 to 300) for all updater processes. The default is 60 seconds.
RDF updaters operate in transaction mode. Updater transactions are essentially long-running
transactions that pin audit trail files on the backup system and can affect the duration of backout
operations if an updater transaction aborts for any reason.
The default value is recommended for RDF environments with heavy updater activity (aggregate
updater throughput greater than 300 kb/second). Raising the
tx-time
in such environments
might adversely affect TMF performance on the backup system.
In RDF environments with low to moderate updater activity and where no other transaction
activity is occurring on the backup system, you could raise the
tx-time
without affecting TMF
performance on the backup system.
The goal of the UPDATERTXTIME is to allow each updater to do as much work as possible in
a single transaction, but not so much work that it would take a long time to undo the transaction,
if that transaction should abort. For this reason the default value of 60 seconds is generally an
optimal value.
UPDATERRTDWARNING Attribute
The UPDATERRTDWARNING attribute specifies the RTD warning threshold (in seconds, 0 or
greater) for all configured updaters. The default is 60 seconds.
This threshold is used by the STATUS RTDWARNING command to determine which updaters,
if any, are to be included in its display. The display includes the monitor process and only those
RDF processes (extractor or updaters) whose RTD exceeds their configured RTD warning
threshold.
UPDATEROPEN Attribute
The UPDATEROPEN attribute specifies the access mode (PROTECTED, PROTECTED OPEN,
or SHARED) that updaters use when opening database files. The default is PROTECTED.
PROTECTED mode is strongly recommended at all times to protect your backup database from
improper write activity by processes other than an RDF updater. PROTECTED mode also allows
user applications to open backup database files for read access but not for write access while the
updater process has the file open. PROTECTED mode, however, is incompatible with taking
online dumps and RELOAD operations. Therefore, if you want to perform one of these two
operations, you need to change UPDATEROPEN from PROTECTED to SHARED. When you
have finished the operation, you should set UPDATEROPEN back to PROTECTED. Previously
you had to stop the updaters before you could change the UPDATEROPEN mode. You can now
do this online, without stopping the updaters.
PROTECTED OPEN is a special variation of PROTECTED. If you have PROTECTED set, it is
possible for the updater to close a file if that file has had no update activity for five or more
minutes. If a rogue user application then opens the file for write access, it is able to write to the
backup database files. If the updater then wants to apply audit from the primary system to that
file, the updater will encounter an error 2 on its REDO operations, and the file will no longer be
in synchronization with the corresponding file on the primary system. The PROTECTED OPEN
mode means that once the updater has opened the file, it will not close the file even if it encounters
a period of idle activity against the file.
SOFTWARELOC Attribute
The SOFTWARELOC attribute specifies where the RDF software is installed on both the primary
and backup systems. The default is $SYSTEM.RDF.
86 Installing and Configuring RDF