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

From: Mike Galbraith
Date: Mon Jul 05 2004 - 10:43:15 EST


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

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