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Date:   Thu, 3 May 2018 13:03:51 -0500 (CDT)
From:   Christopher Lameter <cl@linux.com>
To:     Prakash Sangappa <prakash.sangappa@oracle.com>
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        mhocko@suse.com, kirill.shutemov@linux.intel.com,
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Subject: Re: [RFC PATCH] Add /proc/<pid>/numa_vamaps for numa node
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On Tue, 1 May 2018, Prakash Sangappa wrote:

> For analysis purpose it is useful to have numa node information
> corresponding mapped address ranges of the process. Currently
> /proc/<pid>/numa_maps provides list of numa nodes from where pages are
> allocated per VMA of the process. This is not useful if an user needs to
> determine which numa node the mapped pages are allocated from for a
> particular address range. It would have helped if the numa node information
> presented in /proc/<pid>/numa_maps was broken down by VA ranges showing the
> exact numa node from where the pages have been allocated.

Cant you write a small script that scans the information in numa_maps and
then displays the total pages per NUMA node and then a list of which
ranges have how many pages on a particular node?

> reading this file will not be restricted(i.e requiring CAP_SYS_ADMIN).

So a prime motivator here is security restricted access to numa_maps?