Leo – Hungarian HPC Cluster


The HPC is the newest machines named after Leo Szilard, a Physicist and inventor of the nuclear reactor. The Top500 qualified heavily accelerated machine has 252 Nvidia GPUs to enable running highly accelerated codes to help the 168 Sandy Bridge 8-core CPUs. The system is located at Debrecen, the second largest city in Hungary, and shown in Figure. The machine is integrated to PRACE European HPC network. Other technical information is provided in the table below.

Administrative data

Name Leo
Short Description Hungarian HPC cluster
Owner NIIF Institute
Country Hungary


Dedication to VI-SEEM

CPU (percent) 10%
Storage (percent) 0%
Accelerators (percent) 10%
CPU (core-hours per year) 588,672
Storage in TB 0
Accelerators (hours per year) 125,269,402


System operational since 2015
Available to the project from PM04
Expected date to be phased -
Interfaces SSH


Computational Power

Number of servers 84 Interconnect type FDR InfiniBand Peak performance (Tflops) 248
Server specification HP SL250S Interconnect latency 2.5 μs Real performance (Tflops) 208
CPU per server 2 Interconnect bandwidth 40 Gbps Operating system Red Hat Enterpise Linux
RAM per server 125 GB Local filesystem type Lustre Version 6.5
Total number of CPU-cores 1,344 Total storage (TB) 585 TB Batch system/scheduler SLURM
Max number of parallel processes 2,688 Peak performance CPU (Tflops) - Accelerators type Nvidia K20x and K40x misc.
Number of cores 2688 Servers equipped with accelerators 84 Peak performance accelerators (Tflops) -
Accelerators per server 3
Development tools Intel SDK
Libraries Intel MKL, etc.
Applications Maple, Matlab, etc.