Astronomy and Astrophysics – Astrophysics
Scientific paper
2007-02-06
Astronomy and Astrophysics
Astrophysics
41 pages, 10 figures, accepted for publication in PASP
Scientific paper
10.1086/513572
We describe the development of an FX style correlator for Very Long Baseline Interferometry (VLBI), implemented in software and intended to run in multi-processor computing environments, such as large clusters of commodity machines (Beowulf clusters) or computers specifically designed for high performance computing, such as multi-processor shared-memory machines. We outline the scientific and practical benefits for VLBI correlation, these chiefly being due to the inherent flexibility of software and the fact that the highly parallel and scalable nature of the correlation task is well suited to a multi-processor computing environment. We suggest scientific applications where such an approach to VLBI correlation is most suited and will give the best returns. We report detailed results from the Distributed FX (DiFX) software correlator, running on the Swinburne supercomputer (a Beowulf cluster of approximately 300 commodity processors), including measures of the performance of the system. For example, to correlate all Stokes products for a 10 antenna array, with an aggregate bandwidth of 64 MHz per station and using typical time and frequency resolution presently requires of order 100 desktop-class compute nodes. Due to the effect of Moore's Law on commodity computing performance, the total number and cost of compute nodes required to meet a given correlation task continues to decrease rapidly with time. We show detailed comparisons between DiFX and two existing hardware-based correlators: the Australian Long Baseline Array (LBA) S2 correlator, and the NRAO Very Long Baseline Array (VLBA) correlator. In both cases, excellent agreement was found between the correlators. Finally, we describe plans for the future operation of DiFX on the Swinburne supercomputer, for both astrophysical and geodetic science.
Bailes Matthew
Deller Adam T.
Tingay Steven J.
West Christopher
No associations
LandOfFree
DiFX: A software correlator for very long baseline interferometry using multi-processor computing environments does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with DiFX: A software correlator for very long baseline interferometry using multi-processor computing environments, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and DiFX: A software correlator for very long baseline interferometry using multi-processor computing environments will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-426581