1 Reply Latest reply on Oct 13, 2016 10:22 AM by sophie

    ConnectX-2 IPoIB Performance Help

    dangi12012

      I really need some expertise here:

       

      I have two Windows 10 Machines with two MHQH19B-XTR 40 Gbit Adapters and a QSFP cable in between. The Vlan manager is opensm.

       

      The connection should be about 32Gbits Lan. In reality i only get 5 Gbit performance. So clearly something is very wrong.

      C:\Program Files\Mellanox\MLNX_VPI\IB\Tools>iblinkinfo

      CA: E8400:

            0x0002c903004cdfb1      2    1[  ] ==( 4X          10.0 Gbps Active/  LinkUp)==>       1    1[  ] "IP35" ( )

      CA: IP35:

            0x0002c903004ef325      1    1[  ] ==( 4X          10.0 Gbps Active/  LinkUp)==>       2    1[  ] "E8400" ( )

       

      I tested my IPoIB with a program called lanbench and nd_read_bw:

      nd_read_bw -a -n 100 -C 169.254.195.189

      #qp #bytes #iterations    MR [Mmps]     Gb/s     CPU Util.

      0   512       100          0.843        3.45     0.00

      0   1024      100          0.629        5.15     0.00

      0   2048      100          0.313        5.13     0.00

      0   4096      100          0.165        5.39     0.00

      0   8192      100          0.083        5.44     0.00

      0   16384     100          0.042        5.47     0.00

      0   32768     100          0.021        5.47     100.00

      ..stays at 5.47 after that. with CPU util 100%

      The processor is an intel core I7 4790k so it should not be at 100%. According to Taskmanager only 1 Core is actively used.

      Firmware, Drivers, Windows 10 are up to date.

       

      My goal is to get the fastest possible File sharing between two windows 10 machines.

      What could be the problem here and how do I fix it?