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Subject: Re: [RFC/RFT PATCH v3] sched: automated per tty task groups
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Vivek Goyal <vgoyal@redhat.com>
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        Lennart Poettering <mzxreary@0pointer.de>,
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        Balbir Singh <balbir@linux.vnet.ibm.com>
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On Tue, 2010-11-16 at 14:09 -0500, Vivek Goyal wrote:

> I think this might create some issues with controllers which support some
> kind of upper limit on resource usage. These hidden group can practically
> consume any amount of resource and because use space tools can't see these,
> they will not be able to place a limit or control it.
> 
> If it is done from user space and cgroups are visible, then user can 
> atleast monitor the resource usage and do something about it.

Its cpu-controller only, and then only for SCHED_OTHER tasks which are
proportionally fair.