Optimization of Scaling, I/O and Node-level Performance on Hawk

Photo of scientists participating in a training course in HLRS's Ruehle Saal
For this hybrid course, please notice the COVID rules below.

In order to increase the efficiency of our users' applications on Hawk, HLRS, HPE and AMD offer this workshop to enhance the node-level performance, I/O and scaling of the codes utilized by participants. By doing so, users can raise the volume as well as quality of their scientific findings while the costs (in terms of core hours) remain constant.

By means of this workshop, you can tweak compiler flags, environment settings, etc. in order to make your code run faster. According to our experience gathered in prior workshops, these “low-hanging fruits” can give you a significant speedup but require only little effort.

Furthermore, you will analyze the runtime behavior of your code, locate bottlenecks, design and discuss potential solutions as well as implement them. All categories of bottlenecks (CPU, memory subsystem, communication and I/O) will be addressed, according to the respective requirements. Ideally, the above steps will be repeated multiple times in order to address several bottlenecks.

Every attending group will be supported during the entire workshop by a dedicated member of the HLRS user support group. In addition, HPE and AMD specialists will be available to help with issues specific to e.g. MPI and the processor.

To make it easy for you to attend, we decided to provide this workshop in a hybrid fashion. Besides meeting in person at HLRS, we will hence also setup breakout rooms in a Zoom session which enable remote participants to communicate as well as share screens and remote control applications with support staff, hence providing the same options of interaction as meeting in person.

Learning outcomes

  • Basic knowledge on important tools to enhance the node-level performance, I/O and scaling of the codes utilized by participants on Hawk.
  • Moreover, practical experience in applying these methods.

Target audience: Groups holding a compute time budget to be used on Hawk.


This hybrid event will take place online and at
HLRS, University of Stuttgart
Nobelstraße 19
70569 Stuttgart, Germany
Room 0.439 / Rühle Saal
Location and nearby accommodations

Start date

Nov 07, 2022

End date

Nov 11, 2022



Entry level


Course subject areas

Performance Optimization & Debugging


Code Optimization



Back to list

Prerequisites and content levels

In order to attend the workshop, you should already have an account on Hawk and your application should already be running on the system. Furthermore, we require that you bring your own code including a test case which is set up according to the following rules:

  • use case selection:
    • When processing the test case, your code should have a behavior and profile which is close to that of current and maybe future production runs.
    • If possible, the test case should be representative for those production runs of your group which consume the largest part of your compute time budget.
  • number of cores:
    • In order to be representative, the test case should be in size comparable to the respective current and maybe future production runs.
    • In order to save valuable resources and to allow for a productive workflow, it should however be as small as possible.
    • So take into account to reduce the size of your test case as long as the profile stays almost constant. This can often be achieved by reducing the simulated domain and keep the computational load per core constant ("weak down scaling").
  • wall time:
    • In order to allow for a productive workflow, the wall time should be a few minutes only.
    • At the same time, it should cover all important parts of the code, i.e. computation, communication and I/O.
    • So take into account to reduce the number of simulated time steps.
Content levels
  • Intermediate level: 1 hour 30 minutes
  • Community-target and domain-specific level: 31 hours

Learn more about course curricula and content levels.

In general the language of instruction is German, but can be changed to English, if required.


HLRS, HPE and AMD user support staff


All times are local times in the central European time zone (Berlin).


  • 08:45-09:00 Drop in to the videoconference
  • 9:00 - 17:30 Workshop (Every attending group will be supported during the entire workshop by a dedicated member of the HLRS user support group. In addition, HPE and AMD specialists will be available to help with issues specific to e.g. MPI and the processor. For more details please reffer to the workshop overview above).


Handouts will be available to participants in terms of PDFs.

On-site course & COVID rules

Besides the content of the training itself, another important aspect of this event is the scientific exchange among the participants. We try to facilitate such communication by

  • offering common coffee and lunch breaks and
  • working together in groups of two during the exercises (if desired by the individual participants and permitted by the COVID-19 rules).

For your safety, we will only allow fully vaccinated or fully recovered or COVID-19 negative tested participants on all days. You must wear a medical face mask or FFP2 mask everywhere on site. If a distance of 1.5 m cannot be guaranteed inside, e.g., if you are working in pairs in exercises, it must be an FFP2 mask. Details can be found on the registration page.

We strongly recommend to choose travel options and hotels with the possibility to cancel (even close to the event) because we might be forced to deliver the course as an online course.

Registration information

Register via the button at the top of this page.

You can book individual days acording to your project needs, a full workshop in this case is not necessary.

If you are registering as a tutor/teaching assistent for this workshop please use TA extension after your name
(i.e., Meterman (TA)) during the registration.


for registration is November 4, 13:00, 2022.


Members of German universities and public research institutes: none
Members of universities and public research institutes within EU or PRACE member countries: none
Members of other universities and public research institutes: 120 EUR
Others: 400 EUR
Our course fee includes coffee breaks (on-site courses only)


Björn Dick phone 0711 - 685 87189, dick(at)hlrs.de
Khatuna Kakhiani phone 0711 685 65796, kakhiani(at)hlrs.de
Tobias Haas phone 0711 685 87223, tobias.haas(at)hlrs.de


HLRS is part of the Gauss Centre for Supercomputing (GCS), which is one of the six PRACE Training Centres (PATCs) that started in Feb. 2012.
HLRS is also member of the Baden-Württemberg initiative bwHPC.
This course is provided within the framework of the bwHPC training program.
This course is not part of the PATC curriculum and is not sponsored by the PATC program.

Official course URL(s)


Related training

All training

April 22 - 25, 2024


May 06 - 07, 2024


May 13 - 17, 2024

Hybrid Event - Stuttgart, Germany

June 03 - 07, 2024

Hybrid Event - Stuttgart, Germany

October 14 - 18, 2024

Stuttgart, Germany