[dot] Success Story: KDE for Science

[Dot Stories]

URL: http://dot.kde.org/1109874088/

From: Michael Renner <renner at kde.org>
Dept: science-vs-religion
Date: Thursday 03/Mar/2005, @19:21

Success Story: KDE for Science
==============================

   How do 250 scientists spend their coffee break at a scientific
conference? They use KDE!  There was a scientific conference, the
Tübinger Perception Conference 2005 (TWK)
[http://www.twk.tuebingen.mpg.de/twk05] at the end of February. Many
scientists from all over the world joined to take part in the symposia
and the poster sessions. Because many scientists are addicted to their
e-mail, the organizers installed an Internet Corner with 3 KDE
Terminals.

     This setup was a little bit special, because one PC served 3
GeForce graphic adapters with 2 TFTs and 1 old SGI monitor, 3 keyboards
and 3 mice attached. Under normal circumstances, you can only attach 1
monitor, 1 keyboard and one mouse to a computer. If you attach more than
these, all keyboards and mice are combined into one!

     But a modern PC is idle most of the time, especially for internet
tasks, and the processor load is not as important as the network speed.
So the idea was to setup one PC with several graphic adapters serving
several terminals with KDE as the GUI.

     To run a multi-localuser X system is not a big problem. The
so-called  backstreet ruby [http://www.ltn.lv/~aivils] provides this
functionality as a simple kernel patch for Linux 2.4 and 2.6.  As soon
as the system is running, a sysctr command breaks up the input device
binding. To speed up the whole system, we also applied the low latency
patch [http://www.zip.com.au/~akpm/linux/schedlat.html], but didn't
measure its effect.

     The 3 X servers in our setup were started automatically by a script
at boot time. No login was necessary, KDE starts up without any user
interaction but with unprivileged user rights. The KDE version was
3.3.1. This is not the most current version but, as this setup was done
in 5 hours, there was little time left to update program versions from
the existing state. Anyhow: 3.3.1 is fancy enough for the scientists to
read online tickers and ssh to their university account to start Pine!

     The biggest challenge for us was to find out which keyboard and
mouse were associated with which monitor. While this was a static
mapping, the mouse mapping changed with every system startup. This
problem was not understood, but finding out which of the 3 mice belonged
to which monitor wasn't so difficult. Because the system was very
stable, this was only necessary three times in total.

     The participants loved the setup and many of them were very
surprised to see one PC with 3 independent monitors. Some of them had a
little hesitation using the printer, although printing is very simple
with KDEPrint [http://printing.kde.org/].
     Nobody reported problems with the desktop, although many of them
use XP for their daily desktop work. The most useful applications like
Mozilla [http://www.mozilla.org/] and Konsole [http://konsole.kde.org/]
(because Pine is still used by many students), devices like USB-stick
and CDROM, were represented by  desktop links.
     Nobody reported performance problems, although the machine wasn't
very fancy:  Processor:      P IV with 2.4 GHz Memory:         1 GB HDD:
           80 GB Graphics:       2x GeForce2 MX/MX 400, 1x  nVidia
Quadro FX 500 NVidia-Version: 0.5336 Keyboards:      2x PS/2 with US
layout, 1x USB with DE layout Mice:           3x USB wheel mouse
Screens:        1x LCD 1024x768, 1x TFT 1600x1200, 1x CRT 1024x768
Sound:          Intel Network:        10 MBits Distribution:   Debian
testing/unstable kernel:         2.4.25 with backstreet ruby and low
latency patches

     We want to improve our Conference Internet Corner next year with
more terminals, more sockets for USB-sticks, digicams and maybe a CD
burner. And, of course, with a more current KDE version. Whether we
should use KDE's Kiosk Mode [http://www.kde.org/areas/sysadmin/] is not
yet decided; we will test the kiosk mode first to see if it fits our
needs.

     With Linux, the backstreet ruby patch and KDE and we got a fine,
sensational and cheap solution for accessing mails and other online
resources at a conference.