perfermance problem about the ib_send_bw test

[shengyang-3390]

I test ib_send_bw for two case on ARM services and IB card.
Case1:numactl -C 64 ib_send_bw -d mlx5_0 -a --iters=1000
Case2:numactl -C 64 ib_send_bw -d mlx5_0 --size=1024 --iters=1000

Case1 perfermance data:
#bytes #iterations BW peak[MB/sec] BW average[MB/sec] MsgRate[Mpps]
1024 1000 0.00 5544.28 5.677340

Case2 perfermance data:
#bytes #iterations BW peak[MB/sec] BW average[MB/sec] MsgRate[Mpps]
1024 1000 0.00 920.13 0.942218

The performance of the case1 is 6 times of case2 performance. What may cause the performance gap?

[dimasique1]

I don't notice such degradation on my setup. What about the other message sizes?

[HassanKhadour]

Closing the Issue, please reopen if repro