Parallelisation of the Wide-Band Wide-Field Spectral Deconvolution Framework DDFacet on Distributed Memory HPC System

4 pages, 3 figures, proceedings of the ADASS XXX (2020) conference, to appear in ASP Conference SeriesInternational audienceThe next generation of radio telescopes, such as the Square Kilometer Array (SKA), will need to process an incredible amount of data in real-time. In addition, the sensitivity of SKA will require a new generation of calibration and imaging software to exploit its full potential. The wide-field direction-dependent spectral deconvolution framework, called DDFacet, has already been successfully used in several existing SKA pathfinders like MeerKAT. DDFacet has been developed and optimized for single node HPC systems. DDFacet is a good candidate for being integrated in the SKA computing pipeline and should therefore be run on a massive multi-node HPC system for real-time performances. The objective of this work is to study the potential parallelism of DDFacet on multi-node HPC systems. This paper presents a new parallelization level for multi-node HPC based on frequency domains. Experimental results with a real data set from LOFAR show an optimal parallelisation of the calculations in the frequency domain allowing to generate a sky image more than 4 times faster. This paper analyses the results and draws perspectives for the SKA use case