Date: Tue, 10 Nov 2015 18:06:12 +0100
From: Max Kellermann <mk@cm4all.com>
To: Tejun Heo <tj@kernel.org>, cgroups@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] cgroup_pids: add fork limit
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	linux-kernel@vger.kernel.org
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On 2015/11/10 16:44, Tejun Heo <tj@kernel.org> wrote:
> On Tue, Nov 10, 2015 at 04:37:46PM +0100, Max Kellermann wrote:
> > There's "cpu" which changes priority
> 
> The cpu controller can limit both in terms of relative weight and
> absolute CPU cycle bandwidth.

No, Tejun, the "cpu" controller does not do what my feature does: like
I said, it only changes the priority, or let's rephrase (to account
for the "absolute CPU cycle bandwith" thing): it changes the amount of
CPU cycles a process gets every period.

But it does NOT put an upper limit on total consumed CPU cycles!  It
will only slow down a frantic process, but it will not stop it.
Stopping it is what I want.  Once process crosses the limits I
configured, there's no point in keeping it running.

You may disagree that the feature I implemented is useful, and you may
not want it merged, but do not say that I missed a kernel feature,
because that's not true.

The Linux kernel currently does not have a feature that can emulate
the fork limit that I implemented.  Useful or not, it doesn't exist.

Max
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