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Date: Wed, 25 Apr 2018 19:55:35 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: mingo@redhat.com, linux-kernel@vger.kernel.org,
        Juri Lelli <juri.lelli@gmail.com>
Subject: Re: [PATCH] sched/rt: Rework for_each_process_thread() iterations in
 tg_has_rt_tasks()
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On Thu, Apr 19, 2018 at 08:29:01PM +0300, Kirill Tkhai wrote:
> tg_rt_schedulable() iterates over all child task groups,
> while tg_has_rt_tasks() iterates over all linked tasks.
> In case of systems with big number of tasks, this may
> take a lot of time.

So you're actually using RT cgroups?

Some of us recently considered removing that thing entirely because most
distro's don't actually use it at all -- and it's broken from a RT POV.

That would then clear the slate to try and implement something new.

But if you're actually using this stuff, that would complicate matters.