[Server-devel] Serving 400+ students w/ a single central XS - ejabberd nightmare?

[Bryan Berry]

On Sun, 2009-03-08 at 13:33 +1300, Martin Langhoff wrote:
> Bryan,
> 
> I'm on the road, apologies if I'm a bit succint...
> 
>  - 400 users are unlikely to be online at the same time, supporting
> all users online at the same time will stress all the infra, so the
> path to success is, I suspect, paved with strategies to define usage
> patterns that avoid clustering everyone at the same time.

But 200-300 users could be online at once. I think it will be too
complicated to tell some of them: "Don't connect to the AP right now,
you may overwhelm ejabberd"

>  - I am working on 0.6 which will let you partition the school --
> instead of @online@, large schools can set moodle+ejabberd in a mode
> where users are in a shared-roster-group defined by their course
> membership in moodle. I've posted on the list and written in the wiki
> about this before if you need more detail.
> 
>  - More users - more RAM to the server :-) and disk space for backups
we can provide that

>  - Do you really have a low latency / high bw conn between the schools
> and the location with the XS? I have the feeling we had this
> conversation before... :-) and I suggested smaller and local, which is
> how the XS is designed to work. That's still my recommendation...

The XS is quite a complicated ensemble of software having an XS at every
school magnifies the administration work. Having a centralized XS for
several schools can dramatically reduce administrative overhead.

Additionally our schools only have about 8 hours of electricity per day.
I am concerned about the XS losing power suddenly multiple times per
day.

We have a relatively low latency connection b/w the schools and the XS.

We have discussed these issues before and I believe that we both came to
the conclusion that Nepal has different requirements than some of the
other pilot schools.

-- 
Bryan W. Berry
Technology Director
OLE Nepal, http://www.olenepal.org