RE: Maximum frequency of re-scheduling (minimum time quantum) que stio n

[Mike Galbraith <efault@gmx.de>]

At 10:18 AM 7/5/2004 -0400, Povolotsky, Alexander wrote:

>Mike - the part of my original question was - what is the minimum "measure"
>(in time ticks or is fraction of the time tick ?) of that "(almost) any time
>? In another words, assuming what is the latency between the moment, when
>the higher priority process (or thread ) is becoming available  to run (and
>assuming that "schedule()" system call is not explicitly called at that time
>...)and the moment when the scheduler STARTS (I am not including context
>switch time into the question here) the process of preemtion (start of the
>context switch). Is this time  settable (at compile time ) ?

Ah, you want wakeup latency numbers.  Sorry, I don't have any.  I believe 
Andrew and Davide both wrote tools for measuring in the wild, a search of 
the archives should turn up something that will give you the numbers you're 
looking for.

If I'm understanding your question, no, there is no latency guarantee.


> >If you're looking for an interface into the scheduler that allows you to
> >twiddle slice length
>
>you mean at the run time (vs compile time), I assume ?

Yes.

         -Mike