[dpdk-users] rte_flow / hw-offloading is degrading performance when testing @ 100G

[Cliff Burdick]

What size packets are you using? I've only steered to 2 rx queues by IP dst
match, and was able to hit 100Gbps. That's with a 4KB jumboframe.

On Thu, Feb 28, 2019, 17:42 Arvind Narayanan <webguru2688 at gmail.com> wrote:

> Hi,
>
> I am using DPDK 18.11 on Ubuntu 18.04, with Mellanox Connect X-5 100G
> EN (MLNX_OFED_LINUX-4.5-1.0.1.0-ubuntu18.04-x86_64).
> Packet generator: t-rex 2.49 running on another machine.
>
> I am able to achieve 100G line rate with l3fwd application (fr sz 64B)
> using the parameters suggested in their performance report.
> (
> https://fast.dpdk.org/doc/perf/DPDK_18_11_Mellanox_NIC_performance_report.pdf
> )
>
> However, as soon as I install rte_flow rules to steer packets to
> different queues and/or use rte_flow's mark action, the throughput
> reduces to ~41G. I also modified DPDK's flow_filtering example
> application, and am getting the same reduced throughput of around 41G
> out of 100G. But without rte_flow, it goes to 100G.
>
> I didn't change any OS/Kernel parameters to test l3fwd or the
> application that uses rte_flow. I also ensure the application is
> numa-aware and use 20 cores to handle 100G traffic.
>
> Upon further investigation (using Mellanox NIC counters), the drop in
> throughput is due to mbuf allocation errors.
>
> Is such performance degradation normal when performing hw-acceleration
> using rte_flow?
> Has anyone tested throughput performance using rte_flow @ 100G?
>
> Its surprising to see hardware offloading is degrading the
> performance, unless I am doing something wrong.
>
> Thanks,
> Arvind
>