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Date: Fri, 8 Mar 2024 11:22:44 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Shradha Gupta <shradhagupta@linux.microsoft.com>, Shradha Gupta
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Subject: Re: [PATCH] net :mana : Add per-cpu stats for MANA device
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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?

Seems unlikely, but if it does work we should enable it for all
devices, no driver by driver.