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Date:   Fri, 15 Jun 2018 09:16:47 -0700
From:   Tejun Heo <tj@kernel.org>
To:     Ivan Zahariev <famzah@icdsoft.com>
Cc:     cgroups@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: Cgroups "pids" controller does not update "pids.current" count
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Hello,

On Fri, Jun 15, 2018 at 07:07:27PM +0300, Ivan Zahariev wrote:
> I understand all concerns and design decisions. However, having
> RLIMIT_NPROC support combined with "cgroups" hierarchy would be very
> handy.
> 
> Does it make sense that you introduce "nproc.current" and
> "nproc.max" metrics which work in the same atomic, real-time way
> like RLIMIT_NPROC? Or make this in a new "nproc" controller?

I'm skeptical for two reasons.

1. That doesn't sound much like a resource control problem but more of
   a policy enforcement problem.

2. and it's difficult to see why such policies would need to be that
   strict.  Where is the requirement coming from?

Thanks.

-- 
tejun