Re: report a bug about sched_rt

From: sen wang
Date: Fri Jul 24 2009 - 11:43:32 EST


2009/7/24 Peter Zijlstra <peterz@xxxxxxxxxxxxx>:
> On Fri, 2009-07-24 at 23:07 +0800, sen wang wrote:
>> 2009/7/24 Peter Zijlstra <peterz@xxxxxxxxxxxxx>:
>> > On Fri, 2009-07-24 at 22:04 +0800, sen wang wrote:
>> >
>> >> just one question:
>> >> if cpu is free and there is running state task, how you do?
>> >> schedule the task up? or schedule idle task up?
>> >
>> > Well, when an RT group is over the bandwidth limit I don't consider them
>> > runnable. Therefore, failing to find any other tasks, we run the idle
>> > task.
>> >
>>
>> you havn't anwser the question: if cpu is free, should we Âschedule the
>> running state task or idle task?
>
> It it not runnable because the group is over its limit.
>
>> face the error and fix it! ok?
>
> Please tone down and re-read the explanations I gave.
>
> The throttle is an H-CBS services for RT task groups, meant to provide
> isolation through a fixed resource guarantee.
>
> Any process actually hitting the throttle means a miss configured system
> -- unless its a temporary overload and you're able to deal with those.
>
> The single group case is simply the trivial case thereof.
>
> Your proposed change does not generalize to such a framework, and while
> it might work with the current code, it doesn't serve a use-case
> considered in this architecture and will render the interface
> inconsistent.
>
> Furthermore, future work in this area will not be able to support your
> changed semantics in a sane fashion.
>
> I've yet to see any coherent explanation of your problem, and quite
> frankly I find your attitude offensive.
>
> As you say, Linux is an open-source effort, and you're free to do with
> your copy as you see fit (provided you stick to the rules stipulated by
> the GPLv2). However as co-maintainer of the mainline scheduler I see no
> reason to entertain your change, nor for that matter to continue this
> discussion.
>
>

sorry for my tone, If you feel hurted. I apologize.

But I still hold my viewpoint. I just want the 100-x time should be
used by running task.
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