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Performance Testing

iperf and iperf3

iperf is a simple tool to let you measure memory-to-memory performance access a network.

Sample commands:

Server:

 iperf -s  
 iperf -s -l 256K -w 4M -D
 iperf -s -u -i 1 -p 5003 -D

Client:

 iperf -c serverhost -i 5 -t 20  
 iperf -c serverhost -i 2 -t 20 -r
 iperf -c serverhost -i 5 -t 20 -w 4M -P 4 -r
 iperf -c serverhost -i 5 -t 60 -w 1M -p 6003
 iperf -c serverhost -u -b 200M -p 5003

On public test hosts, bwctl should be used to ensure only 1 iperf test runs at a time.

Note that iperf results are inconsistent for UDP above 1Gbps. We recommend using nuttcp for high-speed UDP testing.

iperf3 is a new implementation from scratch, with the goal of a smaller, simpler code base, and a library version of the functionality that can be used in other programs. iperf3 is not backwards compatible with iperf2.x

Sample commands:

  • same as above