Performance considerations of a disk hosting lpar Was: Disk: Percent full a performance factor?

On a loosely related note, what performance considerations should one
really watch for on an lpar that does nothing but host disk? For example
on our Power 8's all disk (except to the vios lpars) is hosted by one lpar
of IBM i. This then hosts several lpars of IBM i and AIX.

RACK1HST: Hosts main production lpars
% CPU used . . . . . . . : 66.1
Auxiliary storage:
System ASP . . . . . . : 23277 G
% system ASP used . . : 54.3132
System Pool Reserved Max -----DB----- ---Non-DB---
Pool Size (M) Size (M) Active Fault Pages Fault Pages
1 896.18 369.86 +++++ .0 .0 1.9 1.9
2 6329.73 14.27 145 .2 1.4 6.3 30757
3 811.89 .00 203 .0 .0 .6 2.3
4 81.18 .00 5 .0 .0 .0 .0
Work with Disk Status
Elapsed time: 00:00:37
%
Busy
0
0
0
...
For all 32 SSD units.
Virtual Processors Processing units Memory
(GB)
Minimum Assigned Maximum Minimum Assigned Maximum
Minimum Assigned Maximum
RACK1HST 1 10 20 0.1 0.5 1 4 8
16


RACK2HST: Hosts Mimix lpars and backup Domino lpars.
% CPU used . . . . . . . : 5.1
Auxiliary storage:
System ASP . . . . . . : 22500 G
% system ASP used . . : 64.2344
System Pool Reserved Max -----DB----- ---Non-DB---
Pool Size (M) Size (M) Active Fault Pages Fault Pages
1 781.05 362.50 +++++ .0 .0 3.6 3.6
2 6444.86 14.21 175 .0 .0 5.8 255.6
3 811.89 .00 203 .0 .0 1.5 6.4
4 81.18 .00 5 .0 .0 .0 .0
Work with Disk Status
Elapsed time: 00:00:39
%
Busy
0
0
0
...
For all 30 SSD units.
Virtual Processors Processing units Memory
(GB)
Minimum Assigned Maximum Minimum Assigned Maximum
Minimum Assigned Maximum
RACK2HST 1 10 20 0.1 0.5 1 4 8
12


RACK3HST: Hosts rarely used test lpar and a triple backup of our Domino
lpars.
% CPU used . . . . . . . : 19.7
Auxiliary storage:
System ASP . . . . . . : 5956 G
% system ASP used . . : 45.8444
System Pool Reserved Max -----DB----- ---Non-DB---
Pool Size (M) Size (M) Active Fault Pages Fault Pages
1 691.21 352.51 +++++ .0 .0 .0 .0
2 6534.69 13.31 175 .0 .0 2.0 286.7
3 811.89 .00 203 .0 .0 1.2 8.1
4 81.18 .00 5 .0 .0 .0 .0
Work with Disk Status
Elapsed time: 00:00:29
%
Busy
0
0
0
...
for all 22 spinning disks.
Virtual Processors Processing units Memory
(GB)
Minimum Assigned Maximum Minimum Assigned Maximum
Minimum Assigned Maximum
RACK3HST 1 10 20 0.1 0.5 1 6 8
12



Rob Berendt