x710 open sr-iov, vf increase max queues

[pelucky1412]

Hi, all:

I have two questions:

• How to increase number of interrupts of vf?

After X710 open SR-IOV, by default vf has only 4 queues and interrutps max. From [x710 datasheet](https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/xl710-10-40-controller-datasheet.pdf) , after we change the I40E_DEFAULT_QUEUES_PER_VF from default 4 to 16 in /i40e-2.4.10/src/i40e.h, and change the I40EVF_MAX_REQ_QUEUES from default 4 to 16 in 40evf/src/i40evf.h, we can check vf's combined queue is 16 by using ethool -l, the queue's number is adjustable.

The problem is allocated for vf's interrupts is still 4 by check in /proc/interrupts. From datasheet 7.5.1, allocated for vf's interrupts's number is by reading from nvm. So we change num_vf_int's value by hardcode instead of reading from NVM in i40e/src/i40e_common.c, But vf's interrupts number didn't change.

So how to change vf's interrupt number for suiting with vf's queue?

• Change vf's max queue to 16 example

​By using method changing vf's queue to 16, we insert the vf into OVS+DPDK. Because DPDK didn't need interrupts, we can check vf's 16 receive queues in OVS, by now it's work well. I want to ask do you have test this scene or any clients that have used this before?

I find [i40evf maximum RSS queues reasoning](https://forums.intel.com/s/question/0D50P0000490Wa0SAE/i40evf-maximum-rss-queues-reasoning) in community, we didn't use DCB and the post is no longer reply

Nic's information:

• Hardware: Intel Corporation Ethernet Controller X710 for 10GbE SFP+ [8086:1572]
• Driver: i40e-2.4.10, firmware-version: 6.01 0x80003859 1.1892.0
• i40evf-3.5.13
• Kernel: 4.9.0-0.bpo.6-amd64

Wish for replying! 

[WhyeBee_T_Intel]

Hi Pluck, Thank you for posting in Intel Ethernet Communities. We will further check for you regarding how to increase the number of interrupts, just to double check for the second inquiry are you trying to confirm if changing vf queue then insert OVS+DPDK which works for you is a valid method? Looking forward to your reply to better assist you. Best Regards, Whybe T Intel Customer Support Technician Under Contract to Intel Corporation

[pelucky1412]

Hi, Whybe T,

Thx for replying!

Yes.

After ​changing vf's queue to 16 then insert into OVS+DPDK, performance was significantly enhanced. But we didn't find any paper or information to supporting these, we are afraid it may have some trouble but we didn't find yet. So we want to make sure whether it is a valid method.

Best Regards.

Pluck

[WhyeBee_T_Intel]

HI Pluck, Thank you for the confirmation. We will further check and update you. Best Regards, Whybe T Intel Customer Support Technician Under Contract to Intel Corporation

[WhyeBee_T_Intel]

Hi Pluck, Please refer to the table listed on page 14 of the document at https://www.intel.com/content/dam/www/public/us/en/documents/release-notes/xl710-ethernet-controller-feature-matrix.pdf. 4 queues are supported with interrupts. If you intend to use 16 queues, this can be supported if you use a poll mode driver such as DPDK that does not use interrupts. Hope the above information help. Best Regards, Whybe T Intel Customer Support Technician Under Contract to Intel Corporation

[pelucky1412]

Hi, Whybe T,

Thx for replying!

Your reply is very useful!!!

From [x710 datasheet](https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/xl710-10-40-controller-datasheet.pdf)  page 817:

>      The “table size” parameters is loaded from a global MSI_X_PF_N and MSI_X_VF_N parameters in the GLPCI_CNF2 register (loaded from the NVM), shared for all PFs and all VFs respectively.  

Can we increase interrupt number by upgrading NVM or Intel would support this in future?

Best Regards.

Pluck

[WhyeBee_T_Intel]

Hi Pluck, Thank you for the reply. We will need to check on this and will update you once the information is available. Thank you. Best Regards, Whybe T Intel Customer Support Technician Under Contract to Intel Corporation

[WhyeBee_T_Intel]

Hi Pluck, Please submit your request on the driver site at https://sourceforge.net/projects/e1000/, they can better assist you with the request. Hope the information help. Please let me know if you still have other inquiries. Thank you. Best Regards, Whybe T Intel Customer Support Technician Under Contract to Intel Corporation

[WhyeBee_T_Intel]

Hi Pluck, Please feel free to update me if further assistance needed. Thank you. Best Regards, Whybe T Intel Customer Support Technician Under Contract to Intel Corporation