IBM 000-8697 User Manual

Operating OnLine

From the command line, execute the tbparams utility with the -d and
-l

 (lowercase L) option to drop a logical log file.

The -d option indicates you are dropping a log file. When the -d
option is followed by the -l option, the -l introduces the ID number
of the logical log file you are dropping. The following example drops
the logical log file with ID number 121:

tbparams -d -l 121

Create a level-0 archive after your configuration reflects the desired
number of logical log files.

Changing the location of the logical log files is actually a combination of two
simpler actions:

■

Dropping the logical log files from their current dbspace

■

Adding the logical log files to their new dbspace

Although moving the logical logs is easy to do, it can be time-consuming
because you must create two, separate level-0 archives as part of the
procedure.

You can improve performance by moving the logical log files out of the root
dbspace. When OnLine disk space is initialized, the logical log files and the
physical log are placed in the root dbspace. To reduce the number of writes
to the root dbspace and minimize contention, move the logical log files to a
dbspace on a disk that is not shared by active tables or the physical log.

The logical log files contain critical information and should be mirrored for
maximum data protection. If the dbspace to which you are moving the log
files is not already mirrored, plan to add mirroring to the dbspace.