[e2e] TCP performance vs Path MTU

[Zhang Miao]

Hi, Singhvi
    Do you consider the 96b interval between every two Ethernet packets when
analyzing the results? I did a similar experiment two years ago on a 10Mb 
Ethernet link. Only when Ethernet packet length is 64Byte, the total throughput
is less than the link capacity.

>
>This is just a typical sample of what I'm getting on my boxes,
>not any kind of formal benchmark.
>
>Well, a very simple test that varies MTU between 256 and 1500
>on a 100Mb lan between a 400MHz Pentium II and a 866MHz Pentium III
>256 MB using a 3C905C 3COM ethernet adapter shows the following on
>a linux 2.4.2 kernel:
>
>Running a single netperf tcp stream test can saturate the link:
>
>Socket Size (snd, rcv) = 131070 Bytes
>Message Size           = 64 Bytes
>
>MTU Size         Thruput       Confidence
>(Bytes)          Mb/sec        %   # iter
>-------          -------       ----------
>256               68.85         99   15
>300               73.11         99   15
>450               81.74         99   15
>512               83.58         99   15
>536               84.29         99   15
>650               86.85         99   15
>800               89.23         99   15
>1000              91.31         99   15
>1200              92.71         99   15
>1490              94.03         99   15
>1500              94.05         99   15            
>
>You normally wouldnt want to do this...
>
>thanks,
>Nivedita

*****************************************************************
*    Zhang Miao                                                 *
*    Ph.D candidate,Department of Computer Science & Technology * 
*    Tsinghua University,Beijing,China(100084)                  *
*    Tel: (8610)-62785822                                       *
*    Email: zm at csnet1.cs.tsinghua.edu.cn                        *
*    Web: http://netlab.cs.tsinghua.edu.cn/~zm (domestic only ) *
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