Error Checking; Performance Ramifications; Summary Examples - HP NonStop RDF J-series RVUs Management Manual

In the above example, the INCLUDE clause specifies that only audited files in
$DATA01.MMTEST10 are to be replicated. The INCLUDEPURGE clause specifies that every
Enscribe purge operation involving files in this same subvolume are to be replicated, but the
EXCLUDEPURGE clause specifies that any purge operations involving the file
$DATA01.MMTEST10.FILE10 are NOT to be replicated.

Error Checking

Extensive checking is done when the subvolume and file names are parsed, and invalid names
cause errors. The logic of a series of INCLUDE and EXCLUDE clauses, however, is not checked.
For example, information is not regarded as an error, even though it makes no sense because
everything will be filtered out:
SET VOLUME INCLUDE MMTEST10.*
SET VOLUME EXCLUDE MMTEST10.*

Performance Ramifications

The extractor processes all INCLUDE and EXCLUDE clauses. If the extractor reads an audit
record associated with a file or table not specified in an INCLUDE clause, it discards the record.
Similarly, if the extractor reads an audit record associated with a file or table specified in an
EXCLUDE clause, it discards the record.
With volume-level replication, the extractor needs to test only the volume name to determine if
a record should be sent to the backup system. With subvolume- and file-level replication, however,
the extractor must also test the subvolume name and filename. Hence there is more work to do
with subvolume- and file-level replication. If you use large numbers of INCLUDE and EXCLUDE
clauses for each volume, the extractor might have to evaluate the subvolume name and filename
against multiple lists, which could lead to increased CPU usage by the extractor and lower
extractor performance than with simple volume-level replication. Therefore, you should be
careful about how many INCLUDE and EXCLUDE clauses you specify for each volume. The
use of wildcard characters in subvolume names and filenames can help considerably. For example,
to replicate all of the files within all subvolumes whose names begin with the letters DB, you can
do so with a single INCLUDE clause:
INCLUDE DB*.*

Summary Examples

Consider this updater configuration example, where the primary system is \PRIMARY and the
backup system is \BACKUP:
SET VOLUME CPUS 1:2
SET VOLUME IMAGEVOLUME $IMAGE
SET VOLUME PRIORITY 185
SET VOLUME PROCESS $MM01
SET VOLUME UPDATEVOLUME $DATA01
ADD VOLUME $DATA01
In the above example, all audited files and tables on \PRIMARY.$DATA01 are replicated to
\BACKUP.$DATA01.
Now consider this updater configuration example:
SET VOLUME CPUS 1:2
SET VOLUME IMAGEVOLUME $IMAGE
SET VOLUME PRIORITY 185
SET VOLUME PROCESS $MM01
SET VOLUME UPDATEVOLUME $DATA01
SET VOLUME INCLUDE MMTEST10.*
SET VOLUME EXCLUDE MMTEST10.CONC0826
SET VOLUME INCLUDE DATA*.*
SET VOLUME EXCLUDE DATA*.C*
282 Subvolume-Level and File-Level Replication