Re: [Pybeep-devel] seda checkin

[Gabe W. <gw...@wa...>]

It was pointed out to me that SEDA [1] might not be a great advantage in
Python given Python's global interpreter lock and the way it switches
between threads (ie every ten bytecodes) [2]. I've been thinking about
this a bit and I've decided that we should move forward with a SEDA-based
implementation for the following reasons:

1) I think there is still an advantage for non-os threads or even the GIL
situation in python w/r/t tuning of threads under heavy load, as well as
debugging and monitoring (and unit testing, btw!!!)

2) There is always Stackless Python which may have interesting
interactions with SEDA on its own

3) If this is done right, most of the coding will be event-handlers which
means that the threading model can be SEDA, single (or fixed number)
threads, or even fully multithreaded. And it should be *pluggable* (ie
configurable at runtime). Thats actually quite cool,if one thinks about
it.

4) Profile implementations are going to be implemented with event handlers
no matter what anyway, and functionality exposed by the library will be
exposed through an API which will hide any event-architecture specifics.

Thoughts are *greatly* welcomed, though I expect work to commence quite
soon on the event architecture refactoring. I think this will speed up
development quite a bit, and will make both unit and functional testing
much easier.

	-Gabe

[1] http://www.cs.berkeley.edu/~mdw/proj/seda/
[2] http://www.python.org/doc/current/api/threads.html

On Fri, 24 May 2002, Gabe Wachob wrote:

>
> I checked in the beginning of a SEDA-inspired framework today (in
> lib/seda.py)
>
> It sorta actually works. Doesn't do everything SEDA yet - and it does a
> polling to manage threads (which sucks - should be event based itself).
> Also, "Stages" can only have one incoming sink (which might be all we need
> for pybeep).
>
> Take a look. Its far from tested...
>
> 	-Gabe
>
>

-- 
Gabe Wachob                       gw...@wa...
Personal                       http://www.wachob.com
Founder, WiredObjects    http://www.wiredobjects.com