At TU Wien, we are correlating VLBI sessions on the Vienna Scientific Cluster (VSC-3) which is a collaboration of several Austrian universities that provides supercomputer resources and corresponding services to their users. For our purpose, we installed the Distributed FX (DiFX) software correlator and the Haystack Observatory Postprocessing System (HOPS) on the VSC-3 in June 2016. In the first half of 2019, we will move the correlation to the Vienna Scientific Cluster 4 (VSC-4) where we will have private nodes and storage.
The VSC-3 consists of 2020 nodes comprising more than 32000 cores. It is equipped with a BeeGFS parallel filesystem developed for intensive i/o workloads, thus making it an appropriate computing environment for VLBI correlation. The data transfer is realized with jive5ab enabling data transfer rates of (theoretically) up to 20 Gbits/s into the GEANT network. As part of these activities, we investigate the development of our own tools to close the gap between fringe fitting output and the VLBI module of the Vienna VLBI and Satellite Software (VieVS) which reads vgosDB files as input.
Currently we are correlating:
- AUA sessions, including stations in Australia, South Africa, and New Zealand, and
- European Intensive sessions on the baseline Wettzell to Santa Maria.