Hi Sophie!
I thinkit isthe speed limit. Speed PCI gen2 x8 = 32Gbits, do i understand correctly?
ib_write_bw -d mlx4_0 -F 10.0.0.1 --report_gbits
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RDMA_Write BW Test
Dual-port : OFF Device : mlx4_0
Number of qps : 1 Transport type : IB
Connection type : RC Using SRQ : OFF
TX depth : 128
CQ Moderation : 100
Mtu : 4096[B]
Link type : IB
Max inline data : 0[B]
rdma_cm QPs : OFF
Data ex. method : Ethernet
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#bytes #iterations BW peak[Gb/sec] BW average[Gb/sec] MsgRate[Mpps]
65536 5000 26.37 26.37 0.050290
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