Hi Slava,
thank you for the prompt response. I think the requirements for Packet
Pacing should be added to Table 34.2(?) of the MLX5 docs [1].
Best regards,
Carsten
[1] https://doc.dpdk.org/guides/nics/mlx5.html#mlx5-offloads-support
On 29.01.21 19:04, Slava Ovsiienko wrote:
Hi, Carsten
To use packet pacing capability:
- ConnectX-6DX or above is required
- the NV settings should be configured (set timestamp to real-time UTC)
With best regards,
Slava
-----Original Message-----
From: Thomas Monjalon <[email protected]>
Sent: Friday, January 29, 2021 18:50
To: Carsten Andrich <[email protected]>
Cc: [email protected]; Slava Ovsiienko <[email protected]>
Subject: Re: [dpdk-users] MLX5: Using packet send scheduling / packet pacing
29/01/2021 17:30, Carsten Andrich:
Hello everyone,
I'm trying to use packet send scheduling [1] with DPDK 20.11 and the
MLX5 PMD (NIC: ConnectX-5 MCX516A-CDAT). This patch contains some
additional information on this feature also know as packet pacing [2].
According to MLX5's docs, packet pacing requires the "tx_pp" parameter
[3, CTRL+F: "tx_pp"]. However, when firing up testpmd with that
parameter, it fails as follows:
# dpdk-testpmd -a 81:00.0,tx_pp=500 -- -i ...
EAL: Probe PCI driver: mlx5_pci (15b3:1019) device: 0000:81:00.0
(socket 0)
mlx5_pci: WQE rate mode is required for packet pacing
mlx5_pci: probe of PCI device 0000:81:00.0 aborted after
encountering an error: No such device
common_mlx5: Failed to load driver = mlx5_pci.
EAL: Requested device 0000:81:00.0 cannot be used
The error message originates here [4] and is caused by what to me
appears to be a value read from the NIC [5]. Unfortunately, that
leaves me clueless on how to activate the required "WQE rate mode".
According to the output of ibv_devinfo, my NIC does support packet pacing:
# ibv_devinfo -v 81:00.0
...
packet_pacing_caps:
qp_rate_limit_min: 1kbps
qp_rate_limit_max: 100000000kbps
supported_qp:
SUPPORT_RAW_PACKET
I'd be grateful for any information on how to get packet pacing up and
running. Am I just missing another required option (which is not given
in the docs) or does my NIC lack packet pacing support?
Thank you very much in advance.
Best regards,
Carsten
[1]
https://doc.dpdk.org/api/rte__ethdev_8h.html#a990d8351447a710628cbb24
a
28d3252d [2] https://patches.dpdk.org/patch/73742/
[3] https://doc.dpdk.org/guides/nics/mlx5.html#run-time-configuration
[4]
http://code.dpdk.org/dpdk/v20.11/source/drivers/net/mlx5/linux/mlx5_os
.c#L1278
[5]
http://code.dpdk.org/dpdk/v20.11/source/drivers/common/mlx5/mlx5_devx
_
cmds.c#L748
