Quantifying Benefits of Lossless Compression Utilities on Modern Smartphones

Abstract

-The data traffic originating on mobile computing devices has been growing exponentially over the last several years. Lossless data compression and decompression can be essential in increasing communication throughput, reducing communication latency, achieving energy-efficient communication, and making effective use of available storage. This paper experimentally evaluates several compression utilities and configurations on a modern smartphone. We characterize each utility in terms of its compression ratio, compression and decompression throughput, and energy efficiency for representative use cases. We find a wide variety of energy costs associated with data compression and decompression and provide practical guidelines for selecting the most energy efficient configurations for each use case. For data transfers over WLAN, the best configurations provide a 2.1-fold and 2.7-fold improvement in energy efficiency for compressed uploads and downloads, respectively, when compared to uncompressed data transfers. For data transfers over a mobile broadband network, the best configurations provide a 2.7-fold and 3-fold improvement in energy efficiency for compressed uploads and downloads, respectively.

On effectiveness of lossless compression in transferring mHealth data files

“…For uncompressed file uploads Th.UUP is determined as US/T.UUP; for compressed file uploads the effective upload throughput is Th.CUP = US/(T.UUP/CR + T.C), where CR is the compression ratio. In addition to determining the impact of compression on latency of network transfers, we use our experimental setup [9] to measure the energy consumed when uploading and downloading the mHealth files over a wireless interface (with and without compression/decompression). Instead of reporting the total energy in Joules, we report energy efficiency expressed in megabytes per Joule allowing for easy comparison of compressed and uncompressed data transfers.…”