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Re: The Scheduler
> Marc: What about weakening the definition of priority to allow other
> comparable values such as real numbers or (more specifically) time
> objects? With this, I am sure a RT-SRFI could be written without
> having to undo parts of SRFI-18.
I could see using real numbers for priorities, which would allow
deadlines to be expressed (i.e. you set the priority to
(- (time->seconds deadline)) for threads with deadlines, otherwise you
use a positive value for threads without a deadline).
My only worry is that this prevents certain efficient implementations.
For example, you can't represent the set of runnable threads as a
table of lists of threads indexed by priority (a common way to
implement priorities in other thread systems). Also, with integer
priorities, a system that does not implement priorities can define
(thread-min-priority) and (thread-max-priority) to return the same
integer. However, if priorities are real, then I see no reason to
keep (thread-min-priority) and (thread-max-priority).
Anybody have a strong opinion about this?