The effect of floating-point precision on narrow-band all-sky continuous gravitational-wave search algorithm

摘要

Searches for weak gravitational-wave signals in the noisy data of ground-based interferometric detectors are notoriously difficult and computationally expensive. The following work explores the feasibility of improvements related to the details of software implementation using as an example a particular all-sky search for long-lived (continuous) gravitational waves emitted by rotating non-axisymmetric neutron stars (time-domain F-statistic all-sky search (Astone et al., 2010)). In particular, we re-implement the majority of the code in the OpenCL framework, allowing it to execute on multi-device hybrid platforms. We also study the hypothesis that this code is not computationally bound, but memory bandwidth limited - by reducing the floating-point precision employed on various stages of the pipeline we note substantial performance gains. We report which stages may be computed with reduced accuracy without significant loss of precision to the results. The current implementation will allow its deployment on a much broader range of computing facilities. (C) 2021 Elsevier B.V. All rights reserved.