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Re: extremally important question (on how winapi program works)

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W dniu niedziela, 30 sierpnia 2015 15:12:31 UTC+2 użytkownik Dmitry A. Kazakov napisał:
> On Sun, 30 Aug 2015 03:48:02 -0700 (PDT), fir wrote:
> 
> > W dniu niedziela, 30 sierpnia 2015 09:18:39 UTC+2 użytkownik Dmitry A. Kazakov napisał:
> 
> >> Upon a scheduling event, the scheduler checks if the time quant of the
> >> current thread is expired, if yes, the thread's effective priority is
> >> lowered and it loses the processor for a ready-to-execute thread with a
> >> higher priority. There are tons of scheduling strategies and algorithms for
> >> different purposes.
> >> 
> > this is not the answer i seek ("there is a tons of stategies") - i doubt
> > it,
> 
> Scheduling is an optimization problem. First, there are literally tons of
> objectives, goals optimization has to achieve, e.g.
> 
> - balanced load
> - minimize latency
> - guaranteed serviceability
> - schedulability
> - minimize priority inversion 
> ...
> 
> all more or less mutually exclusive and most of them non-achievable. Which
> is the second point.
> 
> A strategy targets some weighted mix of the goals and the algorithm
> implementing it is only an approximation of.
> 

riding a bike is also "tons of objectives mutaully exclusive" but in reality on some level it is not so hard

at some sustained factor (liek app described and no other heavier tasks) i think it works some easy way (dont think it changes constantly and shadulars draw some chaotic and dynamic trajectory rtc ;/ )

only would like to know how..

According to my thought it could me maybe
reasonable if system would not preempt app if it return controll in regular time slices - only could do that ifapp will not getting back longer time (but i dont know,

wil check those links maybe there s some info there

In general reasonable app imo whould work at the schema as running in some fps/Hz cycles (sorta like 20 - 200 Hz, im not sure if <20 or >200 could be considered reasonable (?) and also should be maybe assumed that do not use 100% of cpu load
(though maybe could be assumed to use up to 95 %) If so system could maybe try to fit its tasks in the the abandoned time
- system could cooperate... :/

Otherwise if this preempting slices qould not be to much long (<1ms) it would be maybe no disaster but if it would be longer it would result in jitter in frame times

(those are all my speculations, though a bit based on observation of my frame times
- in my real apps i do not notice jitter,
sorta like al the system would be executed in abandoned (sleep) time - i was even not noticing it on old one core p4 processor

will see the links in a bit moment of time,
i was already reading something but not found yet strict answer claryfing this view

(should maybe title this thread "extremally important question for understanding winapi apps" 9at it is not maybe extremally important for enybody, but still i find this understanding important)

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Thread

extremally important question (on how winapi program works) fir <profesor.fir@gmail.com> - 2015-08-29 15:23 -0700
  Re: extremally important question (on how winapi program works) "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-08-30 09:18 +0200
    Re: extremally important question (on how winapi program works) fir <profesor.fir@gmail.com> - 2015-08-30 03:48 -0700
      Re: extremally important question (on how winapi program works) "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-08-30 15:12 +0200
        Re: extremally important question (on how winapi program works) fir <profesor.fir@gmail.com> - 2015-08-30 13:38 -0700
          Re: extremally important question (on how winapi program works) "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-08-31 09:49 +0200
            Re: extremally important question (on how winapi program works) Chad <cdalten@gmail.com> - 2015-08-31 16:46 -0700

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