Hi all,
I have a newer version of this patch with netlink implementation ready, to 
support the usecase of per-cpu stats for RSS handling and imbalance 
investigations. Please let me know if we can proceed with that.

Thanks and regards,
Shradha.

On Thu, Mar 14, 2024 at 08:01:24PM +0000, Alireza Dabagh wrote:
> Per processor network stats have been supported on netvsc and Mellanox NICs 
> for years. They are also supported on Windows.
> 
> I routinely use these stats to rule in/out the issues with RSS imbalance due 
> to either NIC not handling RSS correctly, incorrect MSI-X affinity, or not 
> having enough entropy in flows. 
> 
> And yes, I perfectly understand that there are cases that packets received on 
> processor x are processed (in tcp/ip stack) on processor y. But in many 
> cases, there is a correlation between individual processor utilization and 
> the processor where these packets are received on by the NIC.
> 
> -thanks, ali
> (some suggested that I do mention on this thread that I am one of the 
> original inventors of RSS. So there you have it. Personally I don't think 
> that telling people "I invented the damn thing and I know what I am talking 
> about" is the right way to handle this.) 
> -----Original Message-----
> From: Jakub Kicinski <[email protected]> 
> Sent: Thursday, March 14, 2024 12:05 PM
> To: Haiyang Zhang <[email protected]>
> Cc: Shradha Gupta <[email protected]>; Shradha Gupta 
> <[email protected]>; [email protected]; 
> [email protected]; [email protected]; 
> [email protected]; Eric Dumazet <[email protected]>; Paolo Abeni 
> <[email protected]>; Ajay Sharma <[email protected]>; Leon Romanovsky 
> <[email protected]>; Thomas Gleixner <[email protected]>; Sebastian Andrzej 
> Siewior <[email protected]>; KY Srinivasan <[email protected]>; Wei Liu 
> <[email protected]>; Dexuan Cui <[email protected]>; Long Li 
> <[email protected]>; Michael Kelley <[email protected]>; Alireza 
> Dabagh <[email protected]>; Paul Rosswurm <[email protected]>
> Subject: [EXTERNAL] Re: [PATCH] net :mana : Add per-cpu stats for MANA device
> 
> On Thu, 14 Mar 2024 18:54:31 +0000 Haiyang Zhang wrote:
> > We understand irqbalance may be a "bad idea", and recommended some 
> > customers to disable it when having problems with it... But it's still 
> > enabled by default, and we cannot let all distro vendors and custom 
> > image makers to disable the irqbalance. So, our host- networking team 
> > is eager to have per-CPU stats for analyzing CPU usage related to 
> > irqbalance or other issues.
> 
> You need a use case to get the stats upstream.
> "CPU usage related to irqbalance or other issues" is both too vague, and 
> irqbalance is a user space problem.

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