vienna scientific cluster jan zabloudil
Your wish is my command line: Austria's supercomputer adapts to changing user needs
The demands on high-performance computing are changing faster than saying the word “supercomputing.” Jan Zabloudil is one of the experts ensuring that Austria's supercomputer VSC runs smoothly. In this interview, he explains how a tool once reserved exclusively for researchers has become accessible to anyone looking to delve into the world of big data, artificial intelligence, and supercomputing.
Interview by Bettina Benesch
Jan, you have been working at TU Wien and BOKU University since the late 1990s. I’m sure you’ve witnessed some interesting developments during that time. What was it like when Austria's supercomputer was still in its infancy?
Things were certainly less complex than they are today. When I was working on my dissertation around 2001, I was also responsible for our workgroup cluster as a System Administrator. It essentially consisted of networked desktop PCs. We set up the computers in a chamber at the institute on large metal shelves with very makeshift cooling. A classic issue was that on Friday afternoons, after everyone had left, the cooling would fail. Monday morning, everything had to be fixed, so the first thing I had to do was head to the computer chamber to restore the optimal temperature.
What does your job entail today?
Since 2009, I've been ensuring that the Vienna Scientific Cluster (VSC) runs smoothly. Back then, I was one of four system administrators — now I work with over a dozen people because the workload today couldn't be managed by just a few individuals. Our team includes System Administrators, Hardware and Infrastructure Experts, Software Developers, Trainers, User Support Staff, and a Communication Expert. I have a hand in everything to some extent.
How has the work at VSC changed over the years?
Initially, it was just about making sure the computers were running. Over time, complexity increased, with each new addition becoming a specialised field in itself. When I started working at VSC, most of our users were physicists, chemists, mathematicians, climate researchers, and material scientists. They performed simulations that typically require high-performance computing resources, like determining material properties or calculating airflows around aircraft parts. Our systems run on Linux, and all traditional users were comfortable with the Linux command line.
Around 2014, the requirements changed significantly. Younger researchers increasingly relied on optimised libraries for performance-related tasks. New scientific disciplines emerged, especially bioinformatics, which had completely different requirements for an HPC environment or computing power.
Since around 2020, we have been getting new users from social sciences and even businesses, working on tasks like optimising traffic routes for emergency services, analysing social networks, or automating text analysis — often using artificial intelligence (AI). Each of our users has different needs, using various codes and programming languages. Many require a ready-made, ideally graphical user interface to carry out their tasks. Our job is to ensure they all can do their work effectively.
“
Around 2014, the requirements changed significantly. Today each of our users has different needs, using various codes and programming languages. Our job is to ensure they can all do their work effectively.
„
HPC is constantly evolving. What's the next big step for the VSC and its users?
The next big step is AI-specific applications that can be launched directly in a web browser. That's the direction we're heading in, though it will take some time before this becomes widely available. Another area we expect to improve is data security, a key priority for many companies.
High-performance computing is gaining more traction in Austria. Does this come with technical challenges?
Energy efficiency is a major concern. The power of supercomputers increases exponentially every few years by a factor of a thousand, but energy consumption cannot rise at the same rate. We need a flatter curve. The latest GPU processors are already more energy-efficient than standard processors, and cooling technology is improving as well. Our current high-performance computers, VSC-4 and VSC-5, consume between 5 and 20 kilowatts for cooling per 100 kilowatts of computing power, depending on the season. This is a significant improvement compared to VSC-1, where cooling accounted for up to 40% of total energy consumption.
“
The power of supercomputers increases exponentially every few years, but energy consumption cannot rise at the same rate. We need a flatter curve.
„
The new Austrian supercomputer MUSICA will go into operation soon. What can users look forward to?
MUSICA (Multi-Site Computer Austria) will be distributed across three locations: Vienna, Linz, and Innsbruck. This presents a technological challenge but also fosters collaboration between universities. The system will mainly run on GPUs, making it ideal for users who want to run AI applications.
What is the difference between computing on the VSC or MUSICA compared to a cloud provider like Google?
Google and other private providers only cover part of what the VSC offers and are more expensive. Those dealing with very large data sets can't rely on the cloud alone.
Additionally, companies using cloud services must send their data to Google, Amazon, or Microsoft, which raises concerns about where the data is stored and what happens to it. Users of the VSC can be confident that their data stays in the country and remains secure.
“
Google and other private providers only cover part of what the VSC offers and are more expensive. With us, data stays in the country and remains secure.
„
Bio box
Jan Zabloudil studied physics at TU Wien, where he also completed his dissertation and worked as a postdoc around the turn of the millennium. Austria’s current supercomputer, the Vienna Scientific Cluster (VSC), was first put into operation in Vienna in 2009, and Jan was one of the first System Administrators to manage it. Today, the team has grown to 17 members, and Jan supports them as a Senior System Administrator and Team Coordinator.
Austria's Supercomputers since 2000
At the beginning of the millennium, there was no large Austrian supercomputer like today's Vienna Scientific Cluster (VSC). Each university institute had its own computing cluster, and there was a larger system at the University of Vienna called "Schrödinger," which operated from 2002 to 2009 in three stages. Schrödinger's successor was VSC-1, a joint project of the University of Vienna, TU Wien, and BOKU University, which went into operation in 2009. Currently, Austria's researchers and entrepreneurs use VSC-4 and VSC-5. In 2025, the new supercomputer MUSICA will be launched, primarily for AI applications.
About the key concepts
Believe it or not, High-Performance Computing (HPC) is actually a relatively old concept: the word "supercomputing" was first used in 1929, and the first mainframe computers appeared in the 1950s. However, they had far less capacity than today's mobile phones. The technology really took off in the 1970s.
HPC systems are used whenever the personal computer's memory is too small, larger simulations are required that cannot be run on the personal system, or when what was previously calculated locally now needs to be calculated much more frequently.
The performance of supercomputers is measured in FLOPS (Floating Point Operations Per Second). In 1997, a supercomputer achieved 1.06 TeraFLOPS (1 TeraFLOPS = 10^12 FLOPS) for the first time; Austria's currently most powerful supercomputer, the VSC-5, reaches 2.31 PetaFLOPS or 2,310 TeraFLOPS (1 PetaFLOPS = 10^15 FLOPS). The era of exascale computers began in 2022, with performance measured in ExaFLOPS (1 ExaFLOPS = 10^18 FLOPS). An ExaFLOPS equals one quintillion floating-point operations per second.
As of June 2024, there were only two exascale systems in the TOP500 list of the world's best supercomputers: Frontier at Oak Ridge National Laboratory and Aurora at Argonne National Laboratory, both in the USA. In Europe, there are currently three pre-exascale computers, which are precursors to exascale systems. Two European exascale systems will be operational shortly.
VSC (Vienna Scientific Cluster) is Austria's supercomputer, co-financed by several Austrian universities. The computers are located at the TU Wien university in Vienna. From 2025, the newest supercomputer, MUSICA (Multi-Site Computer Austria), will be in use at locations in Vienna, Linz, and Innsbruck.
Researchers from the participating universities can use the VSC for their simulations, and under the EuroCC programme, companies also have easy and free access to computing time on Austria's supercomputer. Additionally, the VSC team is an important source of know-how: in numerous workshops, future HPC users, regardless of their level, learn everything about supercomputing, AI and big data.