Re: [RESEND RFC PATCH 0/1] CAP_SYS_NICE inside user namespace

[Jann Horn]

On Mon, Nov 18, 2019 at 6:04 PM Prakash Sangappa
<prakash.sangappa@xxxxxxxxxx> wrote:
> Some of the capabilities(7) which affect system wide resources, are ineffective
> inside user namespaces. This restriction applies even to root user( uid 0)
> from init namespace mapped into the user namespace. One such capability
> is CAP_SYS_NICE which is required to change process priority. As a result of
> which the root user cannot perform operations like increase a process priority
> using -ve nice value or set RT priority on processes inside the user namespace.
> A workaround to deal with this restriction is to use the help of a process /
> daemon running outside the user namespace to change process priority, which is
> a an inconvenience.

What is the goal here, in the big picture? Is your goal to allow
container admins to control the priorities of their tasks *relative to
each other*, or do you actually explicitly want container A to be able
to decide that its current workload is more timing-sensitive than
container B's?