[dpdk-dev] [PATCH] app/testpmd: tx pkt clones parameter in flowgen

[David Marchand]

On Sat, Jan 16, 2021 at 10:39 AM Igor Russkikh <irusskikh at marvell.com> wrote:
>
> When testing high performance numbers, it is often that CPU performance
> limits the max values device can reach (both in pps and in gbps)
>
> Here instead of recreating each packet separately, we use clones counter
> to resend the same mbuf to the line multiple times.
>
> PMDs handle that transparently due to reference counting inside of mbuf.
>
> Reaching max PPS on small packet sizes helps here:
> Some data from our 2 port x 50G device. Using 2*6 tx queues, 64b packets,
> PowerEdge R7525, AMD EPYC 7452:
>
> ./build/app/dpdk-testpmd -l 32-63  -- --forward-mode=flowgen \
>   --rxq=6 --txq=6  --disable-crc-strip --burst=512 \
>   --flowgen-clones=0 --txd=4096 --stats-period=1 --txpkts=64
>
> Gives ~46MPPS TX output:
>
>   Tx-pps:     22926849          Tx-bps:  11738590176
>   Tx-pps:     23642629          Tx-bps:  12105024112
>
> Setting flowgen-clones to 512 pushes TX almost to our device
> physical limit (68MPPS) using same 2*6 queues(cores):
>
>   Tx-pps:     34357556          Tx-bps:  17591073696
>   Tx-pps:     34353211          Tx-bps:  17588802640
>
> Doing similar measurements per core, I see one core can do
> 6.9MPPS (without clones) vs 11MPPS (with clones)
>
> Verified on Marvell qede and atlantic PMDs.

Ubuntu 18.04 gcc complains:
https://github.com/ovsrobot/dpdk/runs/1713302522?check_suite_focus=true#step:14:3097

Can you have a look?

-- 
David Marchand