The Bristol HPC Research Group presented two talks at the Arm Research Summit in Austin, TX, Sep 16-18 2019. In the first talk, Prof. Simon McIntosh-Smith presented the latest scaling results from Isambard, the world’s first production Arm-based supercomputer. The paper included the first scaling comparisons between multiple different Arm-based systems: Isambard (a Cray XC50) and Catalyst (an HPE Apollo70 system). Scaling results for GROMACS, OpenSBLI, VASP and OpenFOAM are included. In addition, an updated compiler heatmap is shown, comparing performance across Cray, Arm Clang/LLVM and GNU, when targetting the Arm ISA.

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The full details of the experiments, such as the compilers used and test cases we tried, are detailed in the slides from the talk.

In the second talk, Andrei Poenaru shared results for generating Scalable Vector Extension (SVE) code for a set of HPC mini-apps. Andrei used SVE compilers from Cray (in alpha form), Arm and GNU to explore how many loops were successfully vectorised, and the resulting improvement in dynamic instruction counts. The research also explored the split between scalar, vector contiguous and vector gather/scatter instructions.

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The full slides for Andrei’s SVE talk are also available from this website.

Simon McIntosh-Smith, Professor of High Performance Computing, Head of the HPC Research Group, University of Bristol. Follow @simonmcs on Twitter for more news from the HPC research group in Bristol.