It's true that the current release (as of 2.3beta) of PWS only supports
sequential threads.  There are two efforts to improve that, both documented
off http://pbl.cc.gatech.edu:8080/myswiki.230

- I've posted a couple of pieces of code that makes parallel threads work
in PWS: one that adds multi-threading to the PWS, the other that adds file
locking to Swikis.
- John Han has rewritten the PWS entirely to improve the design.  Not all
of the current 2.3beta features of PWS have been ported to his design
(e.g., not all the various Swiki types are there, but basic Swikis are),
but he does support multi-threading.

John has said that he's working on a further reworked/new webserver for
Squeak which will be HTTP 1.1 compliant.  (John, please correct me if I got
anything wrong here.)

Mark

>G'day!
>
>I am looking at extending PWS by creating a new ServerAction to provide a
>web interface to an expert system engine (which is a standard stateful C
>program).
>
>On my quick look at PWS, it seems to be running one process (loopOnPort:
>portNumber loggingTo: fileName), which when it receives HTTP requests
>calls (eventually) a ServerAction.  Is this as sequential as it looks or
>am I missing something?
>
>My concern is that if getting the result of the expert system engine takes
>a while, then unless the PWS is concurrently handing other sessions, the
>whole website will stop until the engine is finished.
>
>Can PWS run several ServerActions concurrently?
>
>Also, more generally, are processes in Squeak handled with co-operative
>multitasking or pre-emptive? I can't find a yield message - but will a
>higher priority process completely dominate a lower one?
>
>Any help would be appreciated,
>
>Russell


--------------------------
Mark Guzdial : Georgia Tech : College of Computing : Atlanta, GA 30332-0280
(404) 894-5618 : Fax (404) 894-0673 : guzdial at cc.gatech.edu
http://www.cc.gatech.edu/gvu/people/Faculty/Mark.Guzdial.html