topic Re: i40evf maximum RSS queues reasoning in Ethernet Products

i40evf maximum RSS queues reasoning

SHegd2 — Wed, 06 Jun 2018 00:57:09 GMT

I was looking through the i40evf source code, and it seems like the maximum number of queues supported is 4. Is there a reasoning for this? Is there a way to use more, such as 16?

I've seen patches proposing removing a few variables (MAX_QUEUES, which sets the max to 16, but doesn't actually serve a purpose since the RX queues limit is set to 4).

Re: i40evf maximum RSS queues reasoning

idata — Wed, 06 Jun 2018 02:12:56 GMT

Hi Brokotiv,

Thank you for posting in Wired Communities. Just to double check if you are referring to the driver at

https://downloadcenter.intel.com/download/24693/Intel-Network-Adapter-Virtual-Function-Driver-for-Intel-40-Gigabit-Ethernet-Network-Connections

There is an issue stated in our README file regarding increasing the RSS queue may result in code 10 error, you may find the information at https://downloadmirror.intel.com/24693/eng/readme.txt I have posted here for your reference as well:

" Code 10 Error in Device Manager When Intel DCB Installed and RSS Queues Changed to 16 or Greater

-----------------------------------------------------------------------

If the Intel DCB feature is installed, changing the number of Receive Side

Scaling (RSS) queues to 16 or greater may result in a Code 10 error in Device

Manager. To resolve this issue, reinstall the driver from the Intel

installation media. Note that this will reset the RSS queues value to the

default of 8. Do not change the RSS queues to 16 or greater, as doing so will

result in another Code 10 error. Setting RSS queues to a lower value such as 1,

2, or 4 does not cause error."

If this is not the driver you refer to, please provide the link where the driver was posted. Thank you.

Regards,

Sharon T

Re: i40evf maximum RSS queues reasoning

SHegd2 — Wed, 06 Jun 2018 03:19:19 GMT

Hi,

That is indeed the driver used. I was referring to the code here:

https://github.com/torvalds/linux/blob/master/drivers/net/ethernet/intel/i40evf/i40evf.h# L109 linux/i40evf.h at master · torvalds/linux · GitHub

Is this not accurate as to the latest i40evf driver? When I used SR-IOV with the driver, I was only seeing 4 queues enabled by default, and I was not sure how to increase the maximum, to 8 or 16 as mentioned. Using "ethtool -l" showed a maximum of 4 queues. Is there documentation on how to increase this otherwise?

If it helps, I am running this inside an Ubuntu 14.04 VM, running Linux kernel 4.4.0-97-generic. The host the VM is running on is running on Ubuntu 16.04, with Linux Kernel 4.4.0-87-generic.

Thanks for the help.

Re: i40evf maximum RSS queues reasoning

idata — Wed, 06 Jun 2018 08:14:08 GMT

Hi Brokotiv,

Thank you for sharing the information. Can you also share what is the exact model of your network adapter so that I can better assist. Thanks.

Regards,

Sharon T

Re: i40evf maximum RSS queues reasoning

SHegd2 — Wed, 06 Jun 2018 22:15:40 GMT

Hi Sharon,

The NIC is a Ethernet Controller X710 for 10GbE SFP+.

Re: i40evf maximum RSS queues reasoning

SHegd2 — Fri, 08 Jun 2018 20:07:24 GMT

Hi Sharon,

I just wanted to check if you had any updates on this issue.

Re: i40evf maximum RSS queues reasoning

idata — Thu, 14 Jun 2018 05:52:35 GMT

Hi Brokotiv,

We are still checking and will update in case there is any information to share.

Regards,

Sharon T

Intel Customer Support

Agent under contract to Intel

Re: i40evf maximum RSS queues reasoning

idata — Wed, 20 Jun 2018 08:27:46 GMT

Hi Brokotiv,

Can you confirm how many cores/cpus are assigned to the Virtual machine?

Regards,

Sharon T

Intel Customer Support

Agent under contract to Intel

Re: i40evf maximum RSS queues reasoning

SHegd2 — Wed, 20 Jun 2018 21:01:46 GMT

Hi Sharon, 36 cores were assigned to the VM.

Re: i40evf maximum RSS queues reasoning

idata — Thu, 21 Jun 2018 06:21:30 GMT

Hi Brokotiv,

Thank you. We will further check.

Regards,

Sharon T

Intel Customer Support

Agent under contract to Intel

Re: i40evf maximum RSS queues reasoning

idata — Fri, 22 Jun 2018 06:35:03 GMT

Hi Brokotiv,

Hope you don't mind, we need more information below:

Linux kernel log from the host OS
I40e driver version number from the host.
Did customer modified i40e driver?
Linux kernel log from the Guest OS.
I40ef driver version number from the guest.
Did customer modified i40evf driver?
Ubuntu 14.4 VM settings. Number of VCPUS assigned, memory amount assigned, network devices attached, PCI devices attached in pass though mode, etc.

Please provide SSU LOG as some information can be found there. You may visit this link for the SSU tool:

https://downloadcenter.intel.com/product/91600/Intel-System-Support-Utility

Looking forward to you reply. Thank you.

Regards,

Sharon T

Intel Customer Support

Agent under contract to Intel

Re: i40evf maximum RSS queues reasoning

idata — Mon, 02 Jul 2018 08:03:40 GMT

Hi Brokotiv,

Please fee free to provide the requested information.

Looking forward to you reply. Thank you.

Regards,

Sharon T

Intel Customer Support

Agent under contract to Intel