Re: [Question] ixgbe：Mechanism of RSS

[Tony Nguyen]

On 1/7/2025 7:36 PM, Haifeng Xu wrote:
> On 2025/1/8 01:16, Tony Nguyen wrote:

...

> > What's your ntuple filter setting? If it's off, I suspect it may be the Flow Director ATR (Application Targeting Routing) feature which will utilize all queues. I believe if you turn on ntuple filters this will turn that feature off.
>
> Yes, our ntuple filter setting is off. After turning on the ntuple filters, I compare the delta of recieved packets,
> only 0~15 rx rings are non-zero, other rx rings are zero.
>
> If we want to spread the packets across 0~62, how can we tune the NIC setting?
> we have enabled 63 rx queues, irq_affinity and rx-flow-hash, but the 0~15 cpu
> received more packets than others.

As Jakub mentioned earlier, HW RSS is only supported on this device for 
16 queues. ATR will steer bi-directional traffic to utilize additional 
queues, however, once its exhausted it will fallback to RSS, which is 
why CPUs 0-15 are receiving more traffic than the others. I'm not aware 
of a way to evenly spread the traffic beyond the 16 HW supported RSS 
queues for this device.

Thanks,
Tony

> Thanks!