HW timestamping problems on Linux

[OMarc4]

Hi there,

I tried to get HW timestamping with 2 different Intel NIC cards on Linux.

With 82599ES, although ethtool -T says that the card support HW timestamping for rx and tx, I'm unable to get HW timestamp, only the SW one.

With I350 I get the HW timestamps, but when I compare the tx hw timestamp from one PC to the rx hw timestamp from the other PC, both I350 nic being directly connected with 1 meter cable, I see huge variation in difference of times (several 100s of ms).

I expected to have almost the same value between rx and tx timestamp.

I used this code for setting up and reading timestamps :

https://stackoverflow.com/questions/47313383/linux-udp-datagrams-and-kernel-timestamps-lots-of-examples-and-stackoversflow/47329376#47329376

Thanks for any help

[Crisselle_Intel]

Hello OMarc4,

Thank you for posting in Intel Ethernet Communities. 

Please let us check into your query. Rest assured that we will get back to you within 1-3 business days.

Hoping for your patience.

Best regards,

Crisselle C

Intel Customer Support

A Contingent Worker at Intel

[Crisselle_Intel]

Hello OMarc4,

How are you doing today?

Please be informed that we are still checking on this request. We will get back to you to provide an update as soon as possible but not later than 3 business days.

Thank you for your patience and kind understanding on this matter.

Best regards,

Crisselle C

Intel Customer Support

A Contingent Worker at Intel

[Crisselle_Intel]

Hello OMarc4,

We apologize for the delay on this matter. 

Kindly visit the forum link below as this might help on your issue. Please also share the driver version loaded with ethtool -i output on 82599ES.

https://forums.intel.com/s/question/0D50P0000490AcsSAE/accessing-hardware-timestamps-with-sriov?language=en_US

For I350, please refer to the thread below

As stated "Some Ethernet NICs that support PTP only time stamp PTP packets and not all Ethernet traffic"

https://forums.intel.com/s/question/0D50P0000490DTwSAM/which-intel-nics-support-hardware-timestamps-hardstamps?language=en_US

Let us know if you have additional questions and clarifications on this matter.

Awaiting to your response.

Best regards,

Crisselle C

Intel Customer Support

A Contingent Worker at Intel

[Crisselle_Intel]

Hello OMarc4,

We'd like to follow up the requested information for us to continue to check on this matter. In case you you have additional questions and clarifications, please do not hesitate to ask.

Looking forward to hear from you.

Best regards,

Crisselle C

Intel Customer Support

A Contingent Worker at Intel

[Crisselle_Intel]

Hello OMarc4,

Good day!

Please be informed that we will now proceed in closing this inquiry since we haven't received any response from our previous follow up. In case you have any other concern or assistance needed in the future, please feel free to post a new question.

Best regards,

Crisselle C

Intel Customer Support

A Contingent Worker at Intel