Test steps

      1. Config IxNetwork with one switch and two hosts. Set the packet_in messages of the switch, the interval is 50ms, total 1000000 packets, using ICMP or ARP packets.

      2. Start the controller with the features install.

      3. Start the OF protocol of the switch.

      4. Wait until the channel is established and Echo message interaction started.

      5. Start the capture of IxNetwork.

      6. Enable packet_in, wait until all of the packet_in messages are sent and  no packet_out messages receive.

      7. Stop the capture, analyse the messages captured. First verify the number of packet_out message N, N should be equal to 1 million, if N is less than 1 million, restart this test with smaller packet_in rate. Second, calculate the time difference between the first packet_out message and the last packet_out message T, the packet_out rate can be calculated by N/T. Third, calculate the time delay of each packet_in-packet_out pair as t1、t2、t3 ... ... , of course this can be caculate by decentralized way(select ten sets of pairs), at last calculate the latency by t1+t2+t3 ... ... /N.

      8. Clean the configuration of controllers and IxNetwork.

      9. Repeat test step 1-9 for five times.

      10. Restart the test with another packet_in rate.

Test Results

• Packet_out rate and latency

  Packet_in rate (p/s)	Packet_out rate (p/s)	Latency(ms)
  5000	5002	1.13
  10000	10010	0.6
  15000	14999	1.06
  20000	19945	2.49
  25000	24968	0.84
  30000	29876	1.73
  35000	34853	3.56
  40000	40260	6.62
  45000	41425	89.88
  50000	44123	159.55
  55000	45825	227.57
  60000	46168	331.21
  65000	46558	451.97
  70000	47024	540.5
  75000	48766	590.97
  80000	46436	754.88
  85000	48437	810.88
  90000	48586	901.75
  95000	48232	Packet loss occurs
  100000	45921	Packet loss occurs

• Histogram of Packet_out rate

  
  
  

• Histogram of Packet_out latency
  
  
  
  

As we can see from the result, the maximum packet_out rate is 40000-50000 p/s, when the packet_in rate exceeds 40000 p/s, latency will increase with the rate of packet_in greatly increased. When packet_in rate exceeds 90000 p/s, packet loss occurs.

Therefore, we conclude that the best processing performance of packet_out of ONOS is less than or equal to 40000 p/s.