At 10:31 AM -0500 3/5/01, JArchibald at aol.com wrote:
>WRT GaTechies situation, if expanded budget is forthcoming there, and the
>stability of Swikis into the future is a point of interest, does it not make
>sense to run Swikis from GaTech on a spectrum of platforms so as to be able
>to evaluate (and solve some of) problems discovered?

Please note that "expanded budget" means something significantly 
smaller in the academic world than in the corporate world. :-)  We 
have dug up (read: fought hard for) some $9K to replace aging 
workstations and servers in the lab.  Since a decent box for a server 
can be had for $2.5K these days, this feels like riches to us, but 
it's not going to allow us to do a *lot* of exploration.

We're currently running our servers on MacOS, Linux, and Solaris. 
Linux is by far the most stable, with Solaris second (outstanding 
issues: Can't shift display to any XWindows server, still dies 
occasionally without obvious cause, networking hiccups often hang the 
server), and MacOS distant third.  Some of the other groups around 
campus are running Swiki servers on NT and Windows 2000.  While we 
have less direct experience with those servers, reports suggest 
Solaris-level performance on NT and below-MacOS level performance on 
Windows 2000.

The problem with running on a wide spectrum of platforms is that it's 
REALLY hard to fix the bugs that crop up with Servers.  Only rarely 
are they image-level bugs.  Much more often, the VM's networking 
primitives need tweaking.  Only a couple of GaTech Squeakers have 
proficiency at VM building and tweaking, and they can't know the 
networking details of all these platforms.  We get help from 
Squeakers elsewhere (JMM gave us LOTS of help on the MacOS VM a few 
months ago), but it's still a challenge.

Especially because our focus tends to be moving upward these days. 
We tend to treat Comanche and Swiki as nearly "done," and we're 
building tools and explorations on top of them.  The increasing 
number of students and teachers that use our servers expect the 
servers to be up, and we do our studies on use of the Swikis in 
classrooms hoping that server instability isn't going to be a 
variable.  We need to be able to ignore VM-level bugs, and Linux 
seems to be the best platform for us to be doing this.

That said, we haven't made a decision about Minnow yet.  We're going 
to map several of our other MacOS servers (CoWeb, PBL, Triton) to a 
new Linux box we're getting.  We may keep Minnow on MacOS as a place 
to work on making the Mac implementation solid as a server, but 
there's the tension of above: Yes, we'd LIKE to use Macs as 
platforms, but it's getting to be harder to argue for spending 
resources there.

Mark

--------------------------
Mark Guzdial : Georgia Tech : College of Computing : Atlanta, GA 30332-0280
Associate Professor - Learning Sciences & Technologies.
Collaborative Software Lab - http://coweb.cc.gatech.edu/csl/
(404) 894-5618 : Fax (404) 894-0673 : guzdial at cc.gatech.edu
http://www.cc.gatech.edu/gvu/people/Faculty/Mark.Guzdial.html