Ipoib Performance Vs Ethernet Using Netperf; Perform A Throughput Test - HP NC570C User Manual

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IPoIB Performance vs Ethernet Using netperf

# netserver
# netperf -c -C -f g -H 192.168.10.21
TCP STREAM TEST to 192.168.10.21
Recv Send
Socket Socket
Size Size
bytes bytes
87380 16384
# netperf -c -C -f g -H 192.168.0.2
TCP STREAM TEST to 192.168.0.2
Recv Send
Socket Socket
Size Size
bytes bytes
87380 16384
To test the performance characteristics of IPoIB, use a tool called netperf. This utility runs on both
machines with one machine listening on a TCP socket and the other connecting and sending test data.
The listening program is called netserver while the test client is called netperf.
Netperf has many options, but this example just uses the basic TCP stream test for measurements.
1. Install the netperf utility on both the netperf server and client in the test setup.
For more information, refer to the requirements in
2. Start the listener on Server 2:
Example

Perform a Throughput Test

3. Develop a base case for comparison.
a. On Server 1, run netperf across a normal Ethernet interface.
b. For the output below, we used a cross-over cable between the two servers on their Gigabit
Ethernet interfaces:
c. The options entered into netperf mean the following:
• "-c" and "-C" - requests a report of the local and remote CPU utilization metrics
• "-f g" - requests a report of the results in gigabits per second
d. "-H 192.168.10.21" - specifies the host to contact for running the test
Example
4. Read the test results.
The sample results show about wire speed over the Gigabit Ethernet link, with around 20% CPU
utilization on both ends.
Example
Send
Message Elapsed
Size Time
bytes secs.
16384 10.00
5. Run the test over the IPoIB interface, which was previously setup.
Send
Message Elapsed
Size Time
bytes secs.
16384 10.01
The results in this example show about a 28% increase in throughput, but that has come at the
expense of higher CPU utilization on both the sender and receiver. This is because the native
Ethernet card does TCP/IP checksumming in hardware, while the IPoIB interface must use the host
CPU.
Utilization
Send
Throughput local
10^9bits/s % T
0.94 19.10
Utilization
Send
Throughput local
10^9bits/s % T
1.21 33.88
"Hardware and Applications" on page
Service Demand
Recv Send
remote local
% T us/KB
23.70 1.662
Service Demand
Recv Send
remote local
% T us/KB
87.35 2.290
67.
Recv
remote
us/KB
2.062
Recv
remote
us/KB
5.905