Many out-of-order packets are captured by the X710 network adapter using tcpdump

[pinper23]

Hi all,

We have a strange problem.
For the same network traffic, using the 82599 NIC and using the tcpdump to capture packets does not cause disorder, but using the X710 NIC to capture packets does cause many disorders.

82599 NIC captured packets:

X710 NIC captured packets:

Looking further, you can find that the 12th packet in the captured packet of X710 should be the ACK of the 18th packet, but it is received first. There has been no similar problem with the 82599 NIC. The network traffic is not huge, only 600Mbps.

Have you ever had a similar problem? What could be the cause?

System is Debian 11

X710 driver is the latest i40e 2.25.7

82599 driver is the debian 11 default ixgbe driver.

[vij1]

Hello pinper23,

I hope this message finds you well.

Here are some troubleshooting steps to resolve packet loss for Intel® Ethernet Adapters:

- Enable the Receive Side Scaling (RSS) feature on the Intel® Network Adapter.

- Ensure that you have installed the latest driver for the adapter.

- Update the firmware to the latest version for the Intel Network Adapter.

- Configure Flow control settings on both the switch and Intel Network Adapter to Rx & Tx Enabled.

- Use compatible SFP+ Modules, SFP Modules, and Cables.

- Follow the Tuning Throughput Performance guidelines for Intel® Ethernet Adapters.

- Test the Intel Network Adapter on different PCI slots to ensure compatibility and install it in a slot capable of X8.

- Capture data using a different tool for comparison.

- Refer to the Optimizing Performance tuning notes in the Intel Ethernet User Guide for improving multi-port performance in Windows*.

- Adjust RSS settings as needed through RSS configuration.

If you need further assistance or have any questions, please don't hesitate to ask.

Best regards,

Vijay N.

[pinper23]

Hi Vijay,

Thank you for your help. I think I've found the root case of the problem.

The default value of rx-usecs in 82599 NIC is 1，but in X710 NIC the default value is 50.

I change the value from 50 to 1, the problem did not recur. I'm not sure what other effects will this change have.

Regards,

pinper23

[vij1]

Hi pinper23,

I hope you are doing well.

Thank you for your response. Please monitor the system for 24 hours and let us know if any issues arise.

Regards,

Vijay N.

[vij1]

Hello Pinper23,

I hope this message finds you well.

I am writing you a follow-up on the case. could you please provide an update on the previous post.

Regards,

Vijay N.

[vij1]

Hi Pinper23,

I hope this message finds you well.

I am following up on the case. If you need further assistance, please do not hesitate to reply.

Regards,

Vijay N.