Hi,
I'm part of a team that selects a scripting language for a network
device. The decision is not purely technical but I'd like to provide the
technical aspect. Currently the selection roster includes the following
languages: TCL, Javascript, PHP & Python. I should disclose that I'm
predisposed to Python, despite never using it before, but then the decision may
end up as a marketing decision and not a technical decision. I came across
Stackless Python and was enchanted by the possibilities it opened up for the
device.
My two main concerns are with the performance of the device once
scripting is introduced into it and its stability once a reckless user writes
some clueless scripts (infinite recursion and unwarranted inflated storage
comes to mind). Due to performance issues, I'd like to execute user scripts in
the main execution thread of the processing engines to avoid context switches.
The main features I like about Stackless are:
1. The ability to freeze the script on a blocked channel and return to it once
data is made available.
2. The ability to freeze the script after a set number of instructions (time?)
and reschedule it to a subsequent execution slot in the main loop.
3. The ability to pickle a tasklet and transfer it to a different execution
engine, admittedly I can't really see that happening currently but it's a
feature that may prove useful some day.
So now for my questions:
1. Am I missing something? Is there any fundamental reason the concept
shouldn't work?
2. Memory performance:
a. Heap vs. stack allocation can cause extreme performance degradation
if not optimised. Without delving into the details, should I expect a
significant performance dip in comparison with pure Python?
b. Memory usage: Having these multiple frozen scripts assumes that
their memory utilisation is not extreme. Is there a large memory overhead for
each tasklet? How large is a typical frozen tasklet?
c. Should I pickle the tasklet instead of freezing it and then rerun
it. Would that be extremely CPU intensive? Would pickling a tasklet be a great
memory saver? I should note that I expect most scripts to be pretty basic. They
should extend the device functionality but not replace its core functionality.
3. The future: What's Stackless development model in relation to the main
Python branch. Should it continue to be compatible? Are there plans to
integrate stackless into the main Python development branch someday in some
form?
4. Any ideas on how to sell Stackless Python? I've been told that scripting
languages are like a religion, logic does not always enter into the discussion
;-) , but I'm still trying.
Any comments would be greatly appreciated,
Yuval.
_______________________________________________
Stackless mailing list
[email protected]
http://www.stackless.com/mailman/listinfo/stackless
