To answer your original question, yes, I've hit 400Gbps many times provided
there were enough queues/cores. You can also see test 12.2 here achieved
line rate:

https://fast.dpdk.org/doc/perf/DPDK_23_11_NVIDIA_NIC_performance_report.pdf

On Wed, Jul 24, 2024 at 4:58 AM Yasuhiro Ohara <yasu1976@gmail.com> wrote:

> Hi Thomas,
> Thank you for getting back to this.
>
> From what we have seen, it seemed to be rather a Mellanox firmware issue
> than the pktgen or DPDK issue.
> When we were using ConnectX-7 with fw ver 28.41.1000
> on a Core i9 machine, it limited its tx-bandwidth to 100Gbps,
> though the physical max should be 400Gbps.
> If we lower the fw version to  28.39.2048 or 28.39.3004,
> it could send 256Gbps, on the same core i9 machine.
>
> Our bandwidth demonstration event completed successfully,
> so we are fine with the small knowledge.
> I think my colleague can help if someone wants to debug
> further about this issue.
>
> Thank you anyway.
>
> Regards,
> Yasu
>
> 2024年7月23日(火) 2:37 Thomas Monjalon <thomas@monjalon.net>:
> >
> > Hello,
> >
> > I see there is no answer.
> >
> > Did you try with testpmd?
> > I don't know whether it can be a limitation of dpdk-pktgen?
> >
> >
> >
> > 29/05/2024 03:32, Yasuhiro Ohara:
> > > Hi. My colleague is trying to generate 400Gbps traffic using
> ConnectX-7,
> > > but with no luck.
> > >
> > > Has anyone succeeded in generating 400Gbps (by larger than 1500B is
> ok),
> > > or are there any known issues?
> > >
> > > Using dpdk-pktgen, the link is successfully recognized as 400GbE
> > > but when we start the traffic, it seems to be capped at 100Gbps.
> > >
> > > Some info follows.
> > >
> > > [    1.490256] mlx5_core 0000:01:00.0: firmware version: 28.41.1000
> > > [    1.492853] mlx5_core 0000:01:00.0: 504.112 Gb/s available PCIe
> > > bandwidth (32.0 GT/s PCIe x16 link)
> > > [    1.805419] mlx5_core 0000:01:00.0: Rate limit: 127 rates are
> > > supported, range: 0Mbps to 195312Mbps
> > > [    1.808477] mlx5_core 0000:01:00.0: E-Switch: Total vports 18, per
> > > vport: max uc(128) max mc(2048)
> > > [    1.827270] mlx5_core 0000:01:00.0: Port module event: module 0,
> > > Cable unplugged
> > > [    1.830317] mlx5_core 0000:01:00.0: mlx5_pcie_event:298:(pid 9):
> > > PCIe slot advertised sufficient power (75W).
> > > [    1.830610] mlx5_core 0000:01:00.0: MLX5E: StrdRq(1) RqSz(8)
> > > StrdSz(2048) RxCqeCmprss(0)
> > > [    1.929813] mlx5_core 0000:01:00.0: Supported tc offload range -
> > > chains: 4294967294, prios: 4294967295
> > >
> > > Device type:    ConnectX7
> > > Name:           MCX75310AAS-NEA_Ax
> > > Description:    NVIDIA ConnectX-7 HHHL Adapter card; 400GbE / NDR IB
> > > (default mode); Single-port OSFP; PCIe 5.0 x16; Crypto Disabled;
> > > Secure Boot Enabled;
> > > Device:         /dev/mst/mt4129_pciconf0
> > >
> > > Enabled Link Speed (Ext.)       : 0x00010000 (400G_4X)
> > > Supported Cable Speed (Ext.)    : 0x00010800 (400G_4X,100G_1X)
> > >
> > > pktgen result:
> > >
> > > Pkts/s Rx         :              0
> > >            TX         :  8059264
> > >
> > > MBits/s Rx/Tx  :   0/97742
> > >
> > >
> > > Any info is appreciated. Thanks.
> > >
> > > regards,
> > > Yasu
> > >
> >
> >
> >
> >
> >
>