LUMI is a supercomputer located in Kajaani, Finland capable of over 375 petaflops. It has over 200,000 cores across 2560 nodes, each with an AMD CPU and 4 AMD GPUs. LUMI has a total storage of 118 petabytes and costs €144.5 million to build, using 100% hydroelectric energy. It is used for scientific computing through software installed directly or via containers.

1. Presentation: lumi
dept. of computer science

2. Table of contents
Supercomputers
LUMI
Architecture
Operation
Software

3. SUPERCOMPUTER
• A supercomputer is a computer with a high
level of performance compared to a general-
purpose computer. Performance of a
supercomputer is measured in floating-point
operations per second (FLOPS) instead of
million instructions per second (MIPS).

4. LUMI
• The word “lumi” means “snow” in Finnish
• LUMI (Large Unified Modern Infrastructure) is a petascale
supercomputer located at the CSC data center in Kajaani,
Finland.
• The completed system consists of around 200,000 cores,
capable of executing more than 375 petaflops, with a
theoretical peak performance of more than 550 petaflops
• LUMI’s computing power is equivalent to the combined
performance of 1.5 million of the latest laptop computers

5. Architecture
• The LUMI system is supplied by Hewlett Packard Enterprise
(HPE), based on an HPE Cray EX supercomputer
• The GPU partition consist of 2560 nodes, each node with one
64 core AMD Trento CPU and four AMD MI250X GPUs
• Each GPU node features four 200 Gbit/s network interconnect
cards, i.e. has 800 Gbit/s injection bandwidth

6. • LUMI also has a partition with large memory nodes, with a
total of 32 TB of memory in the partition
• In total, LUMI has an astounding storage of 118 petabytes and
an impressive aggregated I/O bandwidth of 2 terabytes per
second
• Space 150 m2
• Cost €144.5M
• Power 8.5 MW
• The computer uses 100% hydroelectric energy

8. Operation
• Half of LUMI’s capacity belongs to the EuroHPC Joint
Undertaking, 20% of which is reserved for industry and SME
use. The other half is shared among the LUMI Consortium
countries, according to each country’s financial contribution.

9. Software
• There are two options for bringing your scientific
software to LUMI:
• Install your scientific software in your home or project
directory. For this we recommend using the
EasyBuild package manager as it is used to manage the
central software stack on LUMI and makes it easy to
install additional software that extends it. Alternatively,
you may use Spack or the container wrapper.
• Bring a Singularity/Apptainer software container and run
it using the Singularity container runtime provided by
LUMI.