Notes
:
y
Capacity metrics are provided for nonsecure and each variation of security policy
y
The table data reflects System i as a server (not a client)
y
VPN measurements used transport mode, TDES, AES128 or RC4 with 128-bit key symmetric cipher and MD5 message
digest with RSA public/private keys. VPN anti-replay was disabled.
y
This is only a rough indicator for capacity planning. Actual results may differ significantly.
y
x, y and z are scaling constants, one for each NetPerf scenario.
88.8
18.7
15.4
10.9
1.0 z
Large Transfer
(Stream) 16K Bytes
27.5
7.6
6.6
5.0
1.0 y
Asym. Connect/Request/Response
(ACRR) 8K Bytes
7.9
3.8
3.6
2.7
1.0 x
Request/Response
(RR) 128 Byte
ESP with TDES /
SHA-1
ESP with
AES128 /
SHA-1
ESP with
RC4 / MD5
AH with
MD5
Nonsecure
TCP/IP
Transaction Type:
VPN Relative Performance
(scaled to Nonsecure baseline)
The SSL and VPN measurements are based on a specific set of cipher methods and public key sizes.
Other choices will perform differently
.
5.6 Performance Observations and Tips
y
Communication performance on Blades may see an increase when the processors are in shared mode.
This is workload dependent.
y
Host Ethernet Adapters require 40 to 56 MB for memory per logical port to vary on.
y
IBM Power 550, 9409-M50 May show 2 to 5 percent increase over IBM Power 520, 9408-M25 due
to the incorporation of L3 cache. Results will vary based on workload and configuration.
y
Virtual ethernet should always be configured with jumbo frame enabled
y
In 6.1 Packet Trainer is defaulted to "off" but can be configured per Line Description in 6.1.
y
Virtual ethernet may see performance increases with Packet Trainer turn on. This depends on
workload, connection type and utilization.
y
Physical Gigabit lines may see performance increases with Packet Trainer off. This depends on
workload, connection type and utilization.
y
Host Ethernet Adapter should not be used for performance sensitive workloads, your throughput can
be greatly affected by the use of other logical ports connected to your physical port on additional
partitions.
y
Host Ethernet Adapter may see performance increases with Packet Trainer set to on, especially with
regard to HEA’s internal Logical Switch and Partition to Partition traffic via the same port group.
IBM i 6.1 Performance Capabilities Reference - January/April/October 2008
©
Copyright IBM Corp. 2008
Chapter 5 - Communications Performance
72
