AIX'ers!

I have a machine that have problems with performance.
Output from vmstat shows:

kthr memory page faults cpu
----- ----------- ------------------------ ------------ -----------
r b avm fre re pi po fr sr cy in sy cs us sy id wa
18 0 8483035 1571613 0 0 0 0 0 0 6499 99823 13804 68 22 4 7
17 1 8482913 1571734 0 0 0 0 0 0 6778 86403 14977 78 13 6 4
8 2 8483831 1570812 0 0 0 0 0 0 6969 79401 16112 67 15 10 8
8 1 8489595 1565047 0 0 0 0 0 0 6191 209083 17598 70 18 6 6
11 1 8482764 1571877 0 0 0 0 0 0 6049 271784 15108 68 20 5 7
10 1 8482126 1572515 0 0 0 0 0 0 6051 73168 14993 57 11 18 13
12 1 8481532 1573107 0 0 0 0 0 0 6081 87441 15317 60 15 13 12
10 1 8481446 1573193 0 0 0 0 0 0 6344 75612 14889 71 14 7 7
16 1 8483620 1571017 0 0 0 0 0 0 7486 65699 16522 74 13 6 7

I believe this machine has serious problems with CPU and not with memory (columns "pi" and
"po" are always 0).

But my question is: Why is the column "us" under CPU so high instead of the column "sy"?

Anybody have other comments to the output?

We run AIX 5.2, HACMP 5 and Oracle9 RAC. (2 node cluster) The other machine has the same
problem too.


TIA!

Arne S