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From: Cong Wang <xiyou.wangcong@gmail.com>
Date: Mon, 18 Jul 2016 10:52:17 -0700
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Subject: Re: [RFC PATCH 00/30] Kernel NET policy
To: Andi Kleen <andi@firstfloor.org>
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On Mon, Jul 18, 2016 at 8:45 AM, Andi Kleen <andi@firstfloor.org> wrote:
>> It seems strange to me to add such policies to the kernel.
>> Addmittingly, documentation of some settings is non-existent and one needs
>> various different tools to set this (sysctl, procfs, sysfs, ethtool, etc).
>
> The problem is that different applications need different policies.
>
> The only entity which can efficiently negotiate between different
> applications' conflicting requests is the kernel. And that is pretty
> much the basic job description of a kernel: multiplex hardware
> efficiently between different users.
>
> So yes the user space tuning approach works for simple cases
> ("only run workloads that require the same tuning"), but is ultimately not
> very interesting nor scalable.

I don't read the code yet, just the cover letter.

We have global tunings, per-network-namespace tunings, per-socket
tunings. It is still unclear why you can't just put different applications
into different namespaces/containers to get different policies.