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Subject: Re: [PATCH] fs/proc: introduce /proc/stat2 file
To:     Davidlohr Bueso <dave@stgolabs.net>
Cc:     akpm@linux-foundation.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, Davidlohr Bueso <dbueso@suse.de>
References: <20181029192521.23059-1-dave@stgolabs.net>
 <0afed890-7c5a-93ee-cdb9-e30775bd9cf1@redhat.com>
 <20181029200050.iejuxckzbm742dmw@linux-r8p5>
 <3c5ba85b-5114-c751-0114-ac2cb64c02ea@redhat.com>
 <20181029203818.pot26ewxbncfrnua@linux-r8p5>
From:   Waiman Long <longman@redhat.com>
Organization: Red Hat
Message-ID: <b40690db-273f-ff67-01bf-de0111deb499@redhat.com>
Date:   Mon, 29 Oct 2018 16:59:03 -0400
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On 10/29/2018 04:38 PM, Davidlohr Bueso wrote:
> On Mon, 29 Oct 2018, Waiman Long wrote:
>
>> BTW, since you are making stat2 compatible with stat, will that be
>> easier from the user API perspective if we use a sysctl parameter to
>> turn on and off IRQs reporting for /proc/stat, for example?
>
> For one /proc/stat is also common for debugging envs (ie: performance)
> and I fear that if a tunnable modifies the behavior of the output, we
> it might never be usable again (at least not without having users also
> now consider the systctl parameter). Making it dynamic I think is not
> worth it.
>
> Thanks,
> Davidlohr

This is just a matter if it is easier for users to modify their code to
use /proc/stat2 or turning on a sysctl parameter. Again, this will
certainly depend on the circumstances.

Cheers,
Longman