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Date: Mon, 27 Nov 2017 22:46:03 +0300
From: Alexey Dobriyan <adobriyan@gmail.com>
To: mikpelinux.gmail.com@avx2
Cc: linux-kernel@vger.kernel.org, mhocko@kernel.org, willy@infradead.org,
        ak@linux.intel.com, linux-mm@kvack.org
Subject: Re: [PATCH] mm: disable `vm.max_map_count' sysctl limit
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> vm.max_map_count

I always thought it is some kind of algorithmic complexity limiter and
kernel memory limiter. VMAs are under SLAB_ACCOUNT nowadays but ->mmap
list stays:

	$ chgrep -e 'for.*vma = vma->vm_next' | wc -l
	41

In particular readdir on /proc/*/map_files .

I'm saying you can not simply remove this sysctl.