Re: [PATCH RESEND v4] sched/fair: Add advisory flag for borrowing a timeslice

[Khalid Aziz <khalid.aziz@oracle.com>]

On 12/19/2014 04:57 PM, Thomas Gleixner wrote:
> On Fri, 19 Dec 2014, Khalid Aziz wrote:
>> The queuing problem caused by a task taking a contended lock just before its
>> current timeslice is up which userspace app wouldn't know about, is a real
>> problem nevertheless.
>
> We know that already.
>
>> My patch attempts to avoid the contention in the first
>> place. futex with adaptive spinning is a post-contention solution that tries
>> to minimize the cost of contention but does nothing to avoid the contention.
>
> I never said that adaptive spinning can solve that problem.
>
> If you would have carefuly read what I wrote, you might have noticed,
> that I said:
>
>       a proper futex like spin mechanism
>
> Can you spot the subtle difference between that phrase and 'futex with
> adaptive spinning'?
>
>> Solving this problem using futex can help only if the userspace lock uses
>> futex.
>
> A really fundamentally new and earth shattering insight.
>
> If you would spend your time to actually digest what maintainers are
> telling you, we might make progress on that matter.
>
> But you prefer to spend your time by repeating yourself and providing
> completely useless information.
>
> What you are missing completely here is that neither me nor other
> maintainers involved care about how you spend your time. But we very
> much care about the time WE waste with your behaviour.

I am sorry that you feel the need to continue to resort to personal 
attacks even after I made it clear in my last response that I was not 
going to pursue this patch. There is no possibility of a productive 
discussion of a solution at this point. I hope someone else can find a 
solution you find acceptable.

Thanks,
Khalid