> Thank.
> Base on below information, why tends to set pi and po to zero
> value ?
> http://www-03.ibm.com/servers/enable...66/page_4.html

As stated: Reading from disk is much slower then from ram.
>
> It is seem that our machine is not memory-bound, It seem that is
> cpu-bound(cpu id time is small)

If you have idle>0 i would say that the system has free computing
resources so its not cpu bound.

According to your posts its looks for me that you have trashing of
file cache - Wait i/o in conjunction with a high sr/fr rate where
cy was even above 0 so your system is memory bound.
See man vmstat for details regarding sr/fr/cy

Your ps says that you are running a database ( progress ? ) which lead
to the conclusion that your system is not tuned for database usages
( usage of the CIO mount option and DB related tuning settings ).

So read the documentation which comes for your database and configure
the database and os accordingly or in case you have more memory - put
it in.

hth
Hajo