[Stackless] priority patch

[Andrew Francis]

Hello Kristjan:

--- On Thu, 11/5/09, Kristján Valur Jónsson <kristjan at ccpgames.com> wrote:

> Yes, with t.priority=True, starvation _can_ occur.  consider this:

This the problem with priority scheduling in general. 


> I plan on trying to do this in a slightly different manner
> now.  As a first step, I'll abstract away the current
> round-robin scheduling behind some central scheduling API so
> that we can then later add stuff such as priority without
> modifying other parts of Stackless.  

This sounds like a great strategy.

> Stackless has been unchanged for some years now, and I do
> think we need to keep it alive by continuing its
> development, adding features, perhaps creating a
> stackless.tools module, etc.

Yes it is about time Stackless evolves. A part of the solution
is to add tools, i.e., a debugger. Another part of the solution
is new language features - I don't see why Stackless could not
add new language features, for instance event handlers. Also for
once and for all, some real analysis concerning I/O. 

Again, I don't see why the following approach could not be used -
prototype features in PyPy. If necessary move the feature to C based
Stackless Python until that day, PyPy is fast enough to do away with
this. 

Cheers,
Andrew