> -----Original Message-----
> From: Jakub Kicinski <k...@kernel.org>
> Sent: Friday, March 8, 2024 2:23 PM
> To: Haiyang Zhang <haiya...@microsoft.com>
> Cc: Shradha Gupta <shradhagu...@linux.microsoft.com>; Shradha Gupta
> <shradhagu...@microsoft.com>; linux-ker...@vger.kernel.org; linux-
> hyp...@vger.kernel.org; linux-r...@vger.kernel.org;
> net...@vger.kernel.org; Eric Dumazet <eduma...@google.com>; Paolo Abeni
> <pab...@redhat.com>; Ajay Sharma <sharmaa...@microsoft.com>; Leon
> Romanovsky <l...@kernel.org>; Thomas Gleixner <t...@linutronix.de>;
> Sebastian Andrzej Siewior <bige...@linutronix.de>; KY Srinivasan
> <k...@microsoft.com>; Wei Liu <wei....@kernel.org>; Dexuan Cui
> <de...@microsoft.com>; Long Li <lon...@microsoft.com>; Michael Kelley
> <mikel...@microsoft.com>
> Subject: Re: [PATCH] net :mana : Add per-cpu stats for MANA device
>
> On Fri, 8 Mar 2024 18:51:58 +0000 Haiyang Zhang wrote:
> > > Dynamic is a bit of an exaggeration, right? On a well-configured
> system
> > > each CPU should use a single queue assigned thru XPS. And for manual
> > > debug bpftrace should serve the purpose quite well.
> >
> > Some programs, like irqbalancer can dynamically change the CPU
> affinity,
> > so we want to add the per-CPU counters for better understanding of the
> CPU
> > usage.
>
> Do you have experimental data showing this making a difference
> in production?
Shradha, could you please add some data before / after enabling irqbalancer
which changes cpu affinity?
>
> Seems unlikely, but if it does work we should enable it for all
> devices, no driver by driver.
There are some existing drivers, like mlx, rmnet, netvsc, etc. using percpu
counters. Are you suggesting we add a common API for all drivers?
Thanks,
- Haiyang
