Did anyone observed a sudden/abrupt jump in performance while working with DPDK rxonly mode, from 11 queues to 12 queues in Mellanox ConnectX-5 100 GbE NIC

Infrastructure & Networking Adapters and Cables
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1

Recently I observed a peculiar behaviour with Mellanox ConnectX-5 100 Gbps NIC. While working on 100 Gbps capture using DPDK Rxonly mode. It was observed that I was able to receive 142 Mpps using 12 queues. However with 11 queues, it was only 96 Mpps, with 10 queues 94 Mpps, 9 queues 92 Mpps. Can anyone explain why there is a sudden/abrupt jump in capture performance from 11 queues to 12 queues?

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Could you run two tests - one with 11 and one with 12, run ‘perf top’ for every test, capture the screen, and post it to the ticket? What are the names of the functions that consumes most of the CPUs?