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Date: Fri, 31 May 2024 15:42:34 -0700
From: Shakeel Butt <shakeel.butt@linux.dev>
To: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: akpm@linux-foundation.org, jpoimboe@kernel.org, 
	kent.overstreet@linux.dev, peterz@infradead.org, nphamcs@gmail.com, 
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Subject: Re: [PATCH v3] vmstat: Kernel stack usage histogram
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On Thu, May 30, 2024 at 08:14:17PM GMT, Pasha Tatashin wrote:
> Hi Shakeel,
> 
> > Couple of questions:
> >
> > 1. In future with your on-demand kstack allocation feature, will these
> > metrics still be useful? (I think so but I want to know your take)
> 
> It depends on how on-demand allocation is implemented. On hardware
> that supports faults on kernel stacks,

Which hardware supports faults on kernel stacks and which do not?

> we will have other metrics that
> show the total number of pages allocated for stacks.

Don't we already have a metric for that i.e. KernelStack in meminfo
which is in kB unit?

One more question: Is there any concern in making
CONFIG_DEBUG_STACK_USAGE not a debug feature i.e. enable in default
kernels instead of just debug kernels?

thanks,
Shakeel