European Processor Initiative (EPI)

European Processor Initiative (EPI)

Official website:

The European Processor Initiative (EPI) is a research project whose aim is to design and implement a roadmap for a new family of European processors for extreme scale computing, high-performance Big-Data and a range of emerging applications.

The EPI project is structured in various streams:

  • Stream 1 will bring up EPI’s first generation processor (Rhea-1) and board, then connect the EPI accelerator (EPAC-v1.0/v1.5) to the board via PCIe to build a hardware prototype on which software will be installed and applications ported. This will serve to validate the first generation of European processors targeted for the HPC market. Simultaneously, a co-design process will take place targeting the second EPI generations (Rhea-2 and EPAC v2) chips to be developed in EPI. Application requirements will be collected and simulation-based architecture analysis performed to identify the best suited design parameters.
  • Stream 2: develops the general purpose processor Rhea, targeting future European exascale supercomputers. The design is based on Arm V1 cores, HBM, DDR5, PCIeG5/CXL/CCIX. This stream also develops an open Common Platform aiming to efficiently interface processors and accelerators in-package, implementing cache coherency, and validating the toolchains and runtime between processors and accelerators.
  • Stream 3: develops the EPAC accelerator processor using fully European IPs based on the RISC-V Instruction Set Architecture (ISA). The EPAC architecture includes RISC-V vector tiles (VTILE), specialized Deep Learning and Stencil accelerators (STX), and variable floating point precision cores (VRP) all carefully engineered in a heterogeneous tile architecture whose subunits comply to the RISC-V standardization efforts.

JSC contribution

The JSC leads Stream 1 and contributes to the validation of the first generation Rhea and EPAC, and to the codesign of their future generations. In particular, JSC develops a gem5 simulation package for the Arm-based Rhea, which enables quantitatively evaluating the impact of different chip designs into the performance and energy efficiency seen by benchmarks and applications.

Contact person at JSC

Prof. Dr. Estela Suarez

Joint Lead of JSC-Division "Novel System Architecture Design"

  • Institute for Advanced Simulation (IAS)
  • Jülich Supercomputing Centre (JSC)
Building 16.4 /
Room 222
+49 2461/61-9110


The EPI project has received funding from the European High Performance Computing Joint Undertaking (JU) under Framework Partnership Agreement No 800928 and Specific Grant Agreement No 101036168 (EPI SGA2). The JU receives support from the European Union’s Horizon 2020 research and innovation programme and from Croatia, France, Germany, Greece, Italy, Netherlands, Portugal, Spain, Sweden, and Switzerland.

European Processor Initiative (EPI)
European Processor Initiative (EPI)
European Processor Initiative (EPI)

Last Modified: 27.05.2022