> I see that this rdma_post_send call gives a big contribute to CPU use on
> client side. Now the CPU usage (%) is about 95%-99%.

CPU utilization is usually related to how you process completions.  If you switch from polling the CQ to using events, the CPU utilization will go down.  This will also result in the latency going up.

> Could you please send me a comment also about the "plateau non stable"
> in graph speed versus buffer size with buffer size > 10^5 bytes?
> (attached files)

This is likely just an artifact of the test and hardware.
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