Dr. Giuliano Taffoni

1. Dr. Giuliano Taffoni INAF – OsservatorioAstronomico di Trieste The ExaNeSt Project European Exascale System Interconnect & Storage MHPC Workshop on High Performance Computing

2. ExaNeSt project • EU Funded project H2020-FETHPC-1-2014 • Overall budget about 7 MEuro • 12 Partners in Europe (6 industrial partners) • Coordinator ManolisKatevenisFORTH (Foundation for Research & Technology – Hellas) MHPC Workshop on High Performance Computing

3. ExaNeSt Objective “Overall strategy to develop a European low-power high-performance exascale infrastructure based on ARM-based micro servers” • System architecture for datacentric Exascale-class HPC • Fast, distributed in-node non-volatile-memory • Storage Low-latency unified Interconnect (compute & storage traffic) • Extreme compute-power density • Advanced totally-liquid Cooling technology (ICETOPE) • Scalable packaging for 64-bit ARM-based Microservers • Real scientific and data-center applications • Applications used to identify system requirements • Tuned versions will evaluate our solutions MHPC Workshop on High Performance Computing

4. Ecosystem for Exascale • EuroServer: Green Computing Node for European microservers • UNIMEM address space model among ARM compute nodes • Storage and I/O shared among multiple compute nodes • ExaNoDe: European Exascale processor-memory Node Design • ARM-based Chiplets on silicon Interposer • ECOSCALE: Energy-efficient Heterogeneous Computing at exaSCALE • Heterogeneous infrastructure (ARM + FPGAs), programming, runEmes • Kaleao: Energy-efficient μServers for Scalable Cloud Datacenters • Startup company, interested to commercialize many of the results MHPC Workshop on High Performance Computing

5. The Consortium MHPC Workshop on High Performance Computing

6. Astrophysics in Exascale Era • New ground based and space instrumentation will open new challengesin Astrophysics • X-Ray Astronomy, Radio Astronomy, Cosmology, AstroParticle, and more • Extrasolar Planetary Systems, Milky Way, Dark Energy and more • INAF is playing a important role in all those experiments. MHPC Workshop on High Performance Computing

7. A new vision for Computing • New experiments require High Throughput Computing (e.g data reduction, Montecarlomodelling, Instrument and so on) and High Performance computing (in-silico experiments). • New Astronomical data centers that provides archives (storage) and computing capabilities (computation close to data) • New algorithms and codes. MHPC Workshop on High Performance Computing

8. The role of exascale computing • HPC is necessary in the Preparatory phase and in Operation phase of each experiment. • Apply to various research fields: Cosmology, Planetary formation, star formation etc. • HPC is mandatory to compare observation with theoretical models: the HPC infrastructure is the theoretical laboratory to test the physical processes. • New experiments require new exascale capable laboratories! MHPC Workshop on High Performance Computing

9. The technology challenge • Design and develop an exascale super computer with high energy efficiency (<60MW), scalable, fault-tolerant and with a low-latency interconnect • ARM Processors and accelerators MHPC Workshop on High Performance Computing

10. Towards the exascale: HW infrastructure Realistic rack-level shared-memory based on Unimem ~15000 MFlops/Watt MHPC Workshop on High Performance Computing

11. Interconnect and Storage • Unified approach: merge inter-processor traffic with major storage traffic (photonic technologies) • Work will cover interconnect within a rack and inter rack connections • Packaging and network topology analyzed together • Support Quality of Service • Isolate flows with different requirements (low latency, high throughput) • Support for queue, flow-control, congestion control, scheduling, monitoring • Keep data close to computing (UNIMEM approach: moving data is expensive) MHPC Workshop on High Performance Computing

12. Total Liquid Cooling ICEOTOPE current solutions Immersed liquid cooled systems based on convection flow Enhancements planned during ExaNeSt Hybrid : phase-change (boiling liquid) and convection flow cooling Electronics immersed in 3M Novec liquid Rack-level “water” circulation MHPC Workshop on High Performance Computing

13. Building a prototype • 3 Chassis within an Iceotope Rack and 27 blades • 81 mezzanine board with 4 connectors • 324 daughter cards that contains an EuroServer • About 4500 ARM 64 bit Cores • 20% of the budged invested in the prototype. • Available at the end of 2018 MHPC Workshop on High Performance Computing

14. Role of applications • Co-design approach • Applications define the requirements for the system • Applications evaluate the solutions • Test the IO and interconnect • Allow the definition of QoS , flow control… • New generation of exascale ready applications MHPC Workshop on High Performance Computing

15. Applications from different domains • Cosmological n-Body and hydrodynamical code(s) suited to perform large-scale, high-resolution numerical simulations of cosmic structures formation and evolution (INAF). • Brain Simulation. Generate spiking behaviours and synaptic connectivity that do not change when the number of hardware processing nodes is varied(INFN) • Weather and climate simulation(ExactLab) • Material science simulations (ExactLab and EngineSoft) • Workloads for database management on the platform and initial assessment against competing approaches in the market(MonetDB) • Virtualization Systems (Virtual Open systems) MHPC Workshop on High Performance Computing

16. Conclusion • Big challenge: producing the first exascale computing resource in Europe. • Big problems to solve: interconnect, storage, data movments, cooling etc.. • Real Scientific applications will drive development, verify the infrastructure, use the prototype. • A new generation of codes will be designed ready for exascale.