[dpdk-dev] DPDKthe packet capture performance increases steeply between 11 Rx queues and 12 Rx queues. Any idea why?

[Rajesh R]

Hi,
We are experimenting with testpmd packet generation and capture at 100 Gbps
on two machines back to back. We are observing a peculiar behaviour
that the packet capture performance increases steeply between 11 Rx queues
and 12 Rx queues. Any idea why?

The details of the setup are given below:
DPDK version: *19.11*
NIC: *Mellanox ConnectX-5 100 GbE *
OS: *RHEL 8.2(kernel *4.18.0-193)
Application: *Testpmd(txonly on generation side and rxonly on capture side)*

*It is observed that  *capture rate increases almost gradually upto* 11 Rx
queues and then increases steeply *to reach line rate *at 12 queues. The
maximum capture rate with 11 Rx queues is around 80 Gbps and with 12 Rx
queues is 99. Gbps.*

*Is it something to do with DPDK ? Or Mellanox specific?*


-- 
Regards

Rajesh R