IBM 000-8697 User Manual

Operating OnLine

Execute tbstat -R to obtain information about the number of buffers in each

LRU

 queue and the number and percentage of the buffers that are modified.

Details about the function of the

LRU

 queues are described on

.

Refer to

 for further information about the tbstat -R output.

Execute tbstat -D to obtain, by chunk, the number of pages read and the
number of pages written.

Refer to

 for further information about the tbstat -D output.

Monitor checkpoint activity to determine if your checkpoint interval
(specified as

CKPTINTVL

 in the configuration file) is appropriate for your

processing environment.

From

DB-M

onitor, select the Status menu, Profile option.

The

Checkpoints

field lists the number of checkpoints that have occurred

since OnLine was brought online.

The

Check Waits

field defines the number of times that a user process (any

user process) waits for a checkpoint to finish. A user process is prevented
from entering a critical section during a checkpoint. For further information
about critical sections, refer to

Refer to

 for a complete explanation of the Profile option.

From DB-Monitor, select the Force-Ckpt menu.

The display lists the time of the last checkpoint and the last time that OnLine
checked to determine if a checkpoint was needed.