[SCore-users-jp] [SCore-users] Something strange in PM/Ethernet Network Trunking

[Chen Hao]

Hello all, I used PMB 2.2.1 to measure SCORE/MPI performance and found 
something string. When I used two 3C905B NICs, I got the results of 
PingPong and Pingping as following:
#---------------------------------------------------
# Benchmarking PingPong
# ( #processes = 2 )
# ( 14 additional processes waiting in MPI_Barrier)
#---------------------------------------------------
       #bytes #repetitions      t[usec]   Mbytes/sec
            0         1000        49.13         0.00
            1         1000        49.89         0.02
            2         1000        50.40         0.04
            4         1000        50.54         0.08
            8         1000        50.86         0.15
           16         1000        52.92         0.29
           32         1000        56.37         0.54
           64         1000        62.83         0.97
          128         1000        75.88         1.61
          256         1000        98.53         2.48
          512         1000       151.50         3.22
         1024         1000       247.95         3.94
         2048         1000       347.78         5.62
         4096         1000       463.81         8.42
         8192         1000       594.80        13.13
        16384         1000      1056.45        14.79
        32768         1000      1754.30        17.81
        65536          640      3122.35        20.02
       131072          320      5992.52        20.86
       262144          160     11469.87        21.80
       524288           80     22598.54        22.13
      1048576           40     44952.29        22.25
      2097152           20     89360.53        22.38
      4194304           10    178679.39        22.39
#---------------------------------------------------
# Benchmarking PingPing
# ( #processes = 2 )
# ( 14 additional processes waiting in MPI_Barrier)
#---------------------------------------------------
       #bytes #repetitions      t[usec]   Mbytes/sec
            0         1000        55.40         0.00
            1         1000        54.75         0.02
            2         1000        52.09         0.04
            4         1000        55.12         0.07
            8         1000        53.07         0.14
           16         1000        58.13         0.26
           32         1000        57.33         0.53
           64         1000        67.17         0.91
          128         1000        79.80         1.53
          256         1000        98.88         2.47
          512         1000       164.32         2.97
         1024         1000       252.47         3.87
         2048         1000      1901.03         1.03
         4096         1000      3520.96         1.11
         8192         1000      2870.28         2.72
        16384         1000     10062.60         1.55
        32768         1000     10718.80         2.92
        65536          640     20858.36         3.00
       131072          320     26830.07         4.66
       262144          160     39868.81         6.27
       524288           80     62836.03         7.96
      1048576           40    108759.45         9.19
      2097152           20    194836.70        10.27
      4194304           10    379412.10        10.54
we could see that pingpong's bandwidth is very poor when packet is from 
2KB to 64KB, what's the matter?

ChenHao
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