1. July 2000 PPNCG Meeting R. Hughes-Jones Performance Measurements of LANs MANs and SuperJANET III This is PRELIMINARY uBaseline data for Grid development uLatency uThroughput / Bandwidth uPacket Jitter uPerformance of 2 Mbit Managed Bandwidth Link uTCP/IP Stream performance

2. July 2000 PPNCG Meeting R. Hughes-Jones Latency uRound trip times measured using Request-Response UDP frames uLatency as a function of frame size èSlope gives sum of individual data transfer rates end-to-end uHistograms of individual measurements  On LAN Latency histograms ~ 2  s wide PC software 0.01  s/byteSun software 0.036  s/byte

3. July 2000 PPNCG Meeting R. Hughes-Jones Latency: Man-DL uATM MAN u7 routers ~0.8ms / router  Router+link 0.4  s/byte uDL-Liv ~10 ms rtt - agreement uSigma ~12 ms

4. July 2000 PPNCG Meeting R. Hughes-Jones Latency: Man-IC uSigma decreases with size 3.4 -> 1.7 ms uPacket loss falls 5 -> 1 %

5. July 2000 PPNCG Meeting R. Hughes-Jones Latency: Man-UCL  Slope 1.84  s/byte uSigma decreases with size 3.7 -> 1.7 ms uPacket loss falls 3 -> 1 %

6. July 2000 PPNCG Meeting R. Hughes-Jones Latency: Man-GLA uSigma decreases with frame size 2.6 -> 2.3 ms uNO Packet loss  DL slope 2.5  s/byte cf min time slope 1.5  s/byte

7. July 2000 PPNCG Meeting R. Hughes-Jones Latency: Man-RAL uSigma 4.5 -> 6.7 ms uNO Packet loss

8. July 2000 PPNCG Meeting R. Hughes-Jones Latency: Man-RAL Managed BW u5 routers ~0.8ms / router  Slope 6.5  s/byte  A 2Mbit link uses 4  s/byte uNO Packet loss uSigma ~ 2.0 ms uSigma 4.5 ->6.7 ms

9. July 2000 PPNCG Meeting R. Hughes-Jones Latency: Man-MC uPink main campus router uBlue NNW – SuperJANET uNice exponential - queuing

10. July 2000 PPNCG Meeting R. Hughes-Jones Bandwidth uSend a burst of UDP frames spaced at regular intervals uVary the frame size and the frame transmit spacing uRecord èThe time to send and the time to receive the frames èThe number received, the number lost, number out of order Zero stats OK done ●●● Get remote statistics Send statistics Send data frames at regular intervals ●●● Time to send Time to receive

11. July 2000 PPNCG Meeting R. Hughes-Jones Bandwidth: Man-DL uATM MAN u10 Mbit link into the ICFA PC uNo frames lost when not queuing

12. July 2000 PPNCG Meeting R. Hughes-Jones Bandwidth: Man-IC uNNW – ATM WAN – London Man u1-2% frame loss when not queuing for all frame sizes

13. July 2000 PPNCG Meeting R. Hughes-Jones Bandwidth: Man-UCL uNNW – ATM WAN – London Man uSuspect a 10 Mbit link at UCL u1-2% frame loss when not queuing for all frame sizes uIC-UCL frame loss ~0.1%

14. July 2000 PPNCG Meeting R. Hughes-Jones Bandwidth: Man-GLA uNNW – ATM WAN – Glasgow uNO frame loss when not queuing uSimilar behavior to Man-IC

15. July 2000 PPNCG Meeting R. Hughes-Jones Bandwidth: Man-RAL uPC Manc. – NNW – ATM WAN – LAN RAL Sun uOdd bursts of frame loss when not queuing u24 Mbit link into RAL

16. July 2000 PPNCG Meeting R. Hughes-Jones Bandwidth: Man-RAL Managed BW uPC Manc. LAN – ATM PVC – RAL Sun uNO frame loss when not queuing uSuggests PVC iS CBR, given 1 cell every 75

17. July 2000 PPNCG Meeting R. Hughes-Jones Packet Jitter uSame protocol as for the Throughput tests uSend frames at regular fixed time intervals uMeasure the difference between consecutive frame arrivals using the Pentium cycle counter.

18. July 2000 PPNCG Meeting R. Hughes-Jones Packet Jitter: Man-MC PRELIMINARY !! uHEP – gw-metro  Major peaks 160  s  Satellites  40  s  ATM cell 2.74  s ? u1000 byte frames appear to arrive too quickly.

19. July 2000 PPNCG Meeting R. Hughes-Jones Packet Jitter: IC-UCL PRELIMINARY !!  1000  s frame spacing uStructure for 100 byte frames  Satellites at  40  s  ATM cell 2.74  s ?