M. Drosg (until March 31, 2003), Ch. Dellago (from April 1, 2003)

Computer Sciences

Slightly more than 20 years Prof. Drosg has coordinated teaching of computer sciences at the Institute. During this period the volume of teaching computer oriented subjects has increased from 28 semester hours per year in the 1982/83 term to about 110 semester hours per year at the beginning of this millenium.

Part of this increase is due to the evolvement of Computational Physics during this period. So computer sciences are organized from now on inside the Computational Physics division of the Institute which is headed by Prof. Dellago.

One main accomplishment of Prof. Drosg was the establishment of the first PC class room faculty wide at the Institute. Besides his policy of engaging outside lecturers with first-hand knowledge in the rapidly developing field of computer science made it possibly to react rather quickly to new developments. So not only basic courses but also quite demanding courses could be offered. So the courses were in high demand not only in the physics department, but also faculty-wide, university-wide and even with users from other universities.

More details were given in last year's progress report when 30 years of teaching computer sciences at the Institute were celebrated. There, all lecturers are listed who made this success story possible. Due to Prof. Drosg's retirement at the end of this term Prof. Dellago has taken over the responsibility for the teaching of computer sciences.


To improve and streamline the computational science part of the physics curriculum we are teaching both FORTRAN and C in one class (UE 2 hours, Lektor Penits) and for science freshmen a course called "Scientific computing" (VO+UE 4 hours, Prof. Neumann, Dr. Karch), stressing programming languages (FORTRAN, C, Mathematica), basic algorithms (from simple equations through Monte Carlo applications) and various skills (UNIX, Gnuplot, LATEX). A script for this course can be found in the tutorial section of our web-server (http://www.exp.univie.ac.at/inst/skripten.html).

Additional physics connected teaching of computer sciences was done by the Computational Physics Group and within the general curriculum of physics students.

The local PC Class Room Web-Server is behind a firewall making students' homework via Internet rather inconvenient. But this cannot be helped. In the PC Class Room 14 PCs are connected under Novell Netware 5.x working alternately under the operating systems MS-DOS, Windows NT or LINUX.

For lecturing special topics in the field of scientific number crunching (mainly parallel computing/ network computing) there is not only our old Transputer Board System available (mainly to demonstrate flexible/different topologies), but also a Linux-Cluster with 16 Alpha-Processors (each 4 of them grouped in one machine with locally shared memory - suitable for SMP Applications), and our state-of-the-art educational Beowulf-Cluster with five dedicated Linux-MPI PCs based on Athlon technology which resides in our workstation laboratory (WS-Lab). The latter cluster teaches computational physics students how to use today's High-Performance-Computing (HPC) systems like e.g. the "Schroedinger II" cluster (see http://www.univie.ac.at/nic) owned by the faculty and the computing center of the University.

In 2001 we implemented a distributed computing systems called Condor http://www.cs.wisc.edu/condor/ in our PC-Lab. The idea behind Condor is simple. It matches computational jobs of any computer user with spare computing power in other owners' computers. Condor acts as a matchmaker between the jobs and the machines by pairing the requirements of a job with the available resources of a set of machines (the rule set is highly customizable).

Our cluster (see http://condor.exp.univie.ac.at/, for users behind the ZID-firewall, only) consists of a Linux central manager and NT/W2k/XP clients (mainly from our PC-Lab) connected by our LAN. Around the clock it is used mainly for jobs requiring much CPU time like Monte Carlo based Research Activities. Using normal user workstations is very cost-effective because such workstations are used by their owners, even in prime time to less than 5% of the time. (Ian Foster, the guru on Grid-Computing, calls systems like Condor a "first-generation" computing Power Grid http://www.globus.org/). This new type of number crunching is also called HTC (high throughput computing).

Contrary to HPC (which is based on dedicated, homogenous, high-end systems which have a well known performance expressed in operations/second) HTC is based on non-dedicated, heterogeneous, and distributed systems, connected via normal networks allowing only a statistically description of the performance (e.g. floating point operations per month).

The Workstation ClassRoom in the building Sensengasse 8 is used for Practical Courses, and for Diploma works in the field of Computational Physics. There are two clusters with classical "workstations" available: a DEC Alpha-Cluster with a DEC 3000-400 and five DEC 3000-300Ls under OpenVMS. However, teaching there is now mainly done under a PC-based multi-processor LINUX Computer.

Aside from the local computers, those of the local branch of the Central Computing Division of the University of Vienna (AP des ZID der Universität Wien) running under UNIX, or any other computer accessible via INTERNET (like the OPEN-VMS cluster of the Institute which is, however, supposed to phase out in October 2003) are available for all students working either in the PC Class Room or the Workstation Class Room.


Since March 1995 the Institut für Experimentalphysik has been present in World Wide Web (WWW) with the address: http://www.exp.univie.ac.at. This service was made possible by the endeavor of Prof. Neumann who is still in charge of it and who is spending some of his valuable time on rather frequent updates of it.