Accelerating a Cloud-Based Software GNSS Receiver

Abstract

This paper discusses ways to reduce the execution time of a software Global Navigation Satellite System (GNSS) receiver that is meant for offline operation in a cloud environment. Client devices register satellite signals they receive, and send them to the cloud, to be processed by this software. The goal of this project is for each client request to be processed as fast as possible, but also to increase total system throughput by making sure as many requests as possible are processed within a unit of time. The characteristics of the application provided both opportunities and challenges for increasing performance. This paper describes the speedups we obtained by enabling the software to exploit multi-core CPUs and GPGPUs. It mentions which techniques worked and which did not. To increase throughput, it describes how to control the resources allocated for each invocation of the software to process a client request, such that multiple copies of the application can run at the same time. It uses the notion of the effective running time to measure the system's throughput when running multiple instances at the same time, and show how to determine when the system's computing resources have been saturated.