Re: Comments on the KSE option

On Saturday 28 October 2006 12:36, Julian Elischer wrote:
Julian

As you are emphasizing fairness, I must say I don't believe fairness in
libpthread either,

you mean you don't think it is a good idea or that you don't think it
works? (sorry, I know that your english is way better than my
chinese ;-)

I meant I don't think libpthread's userland scheduler + ksegrp in kernel
has implemented fairness between threads correctly.

I don't think writing a fairness scheduler is an
easy work, does kernel have made fairness for threads in same ksegrp,
so does libpthread's userland scheduler ?

The kernel is only responsible for making sure that one ksegrp
(usually a process in my original idea) is not unfair to another
ksegrp.
What happens within the ksegrp is not it's interest. And no it
isn't an easy thing to do which is why I had hoped that some
PhD student would have taken it up by now :-)

they don't, it can make threads
in same ksegrp misbehaviored, so what we have done is still process
scheduling fairness even there is ksegrp in kernel, and now sacrificed
fairness between threads.

once again, I'm not sure what you mean by that.

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