Instances of lazy scheduling and timeslice donation in L4 implementations

Sergio Ruocco sruocco at
Wed Jan 25 02:14:46 CET 2006

Kevin Elphinstone wrote:
> Arrgghhh, here we go again.... I don't have enough time in my life
> for yet another scheduling debate, so I'll summarize my view in the
> hope

Probably the second classic debate after Emacs vs vi !

> So rather than argue over details of how lazy-scheduling "should" or

I am just trying to understand what's there in the gulf between
specifications and implementations of L4 scheduling, an area which look
subtly underspecified and/or mis-implemented. The more debate and POV we
get on it, the better.

> And no matter which model you require (except for maybe the first),
> your likely to have to audit the code to confirm your expected
> behaviour if your relying on it.

My specific problem WRT scheduling is that I want to be able to rely on 
behaviour as "in the spec", and not worry about details and 
optimisations in the various implementations, but probably I am 



ERTOS Researcher                                              Lecturer
National ICT Australia Ltd.              University of New South Wales

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