Oracle 10g / AIX performance issue .. excessive paging?

Hi all,

A customer of ours has migrated their database from 8i to 10g recently and onto new hardware and has experienced poor performance since the move.

I ran nmon/topas to get an idea of the top process activity:

┌─topas_nmon──S=WLMsubclasses────Host=bupaidb1───────Refresh=2 secs───09:57.43──────────────────────────────┐
│ Top-Processes-(3093) ────Mode=6  [1=Basic 2=CPU 3=Perf 4=Size 5=I/O 6=Cmds]───────────────────────────────│
│Procs    %usr      %sys     Res      Res      Char Paging Command                                          │
│Total=71                 Text-KB  Data-KB   I/O-KB                                                         │
â&#148;&#130;    1   56.7414   15.8515       0       0        0      0 <defunct Zombie>                                 â&#148;&#130;
â&#148;&#130;    1    7.7053    0.8210     628   32672        1      0 topas_nmon                                       â&#148;&#130;
â&#148;&#130;  706   49.0424    8.0259 28686192 3825220     1645   1125 oracle                                          â&#148;&#130;
â&#148;&#130;    1    2.9740    0.0000       0     256        0      0 lrud                                             â&#148;&#130;
â&#148;&#130;    1    1.1168    0.3420    1116    1368        1    450 tnslsnr                                          â&#148;&#130;
â&#148;&#130;    4   -2.0660    4.7103       0    1280        0    305 wait                                             â&#148;&#130;
â&#148;&#130; 2302    4.9978    0.0000       0  891968        0   2541 aioserver                                        â&#148;&#130; 

Topas Monitor for host:    bupaidb1             EVENTS/QUEUES    FILE/TTY
Wed Aug 12 09:58:04 2009   Interval:  2         Cswitch    9799  Readch  9134.3K
                                                Syscall   41871  Writech 1525.0K
CPU  User%  Kern%  Wait%  Idle%  Physc   Entc   Reads      3460  Rawin         0