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Subject: Re: [RFC PATCH] Add /proc/<pid>/numa_vamaps for numa node information
References: <1525240686-13335-1-git-send-email-prakash.sangappa@oracle.com>
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From: Dave Hansen <dave.hansen@intel.com>
Message-ID: <aaca3180-7510-c008-3e12-8bbe92344ef4@intel.com>
Date: Wed, 9 May 2018 16:31:22 -0700
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To: prakash.sangappa@oracle.com, Anshuman Khandual <khandual@linux.vnet.ibm.com>, Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, mhocko@suse.com, kirill.shutemov@linux.intel.com, n-horiguchi@ah.jp.nec.com, drepper@gmail.com, rientjes@google.com, Naoya Horiguchi <nao.horiguchi@gmail.com>

On 05/07/2018 06:16 PM, prakash.sangappa wrote:
> It will be /proc/<pid>/numa_vamaps. Yes, the behavior will be
> different with respect to seeking. Output will still be text and
> the format will be same.
> 
> I want to get feedback on this approach.

I think it would be really great if you can write down a list of the
things you actually want to accomplish.  Dare I say: you need a
requirements list.

The numa_vamaps approach continues down the path of an ever-growing list
of highly-specialized /proc/<pid> files.  I don't think that is
sustainable, even if it has been our trajectory for many years.

Pagemap wasn't exactly a shining example of us getting new ABIs right,
but it sounds like something along those is what we need.