R3 : reduce, reuse and recycle

Abstract

Every Android application runs in its own virtual machine, with its own Linux user account and corresponding permissions. Although this ensures that permissions are given as per each application’s requirements, each permission itself is still broad enough to possible exploitation. The heap memory can be accessed by default by all apps and can be misutilized to unimaginable extents. Such exploitations may result in an over consumption of phone’s resources, in terms of memory, battery, and communication bandwidth. In this work, we propose a tool called R3, for the app developers and users to control application’s permissions at a fine granularity thereby reducing the exploitation of permissions. We provide the developers an opportunity to recycle the objects that are short lived and created in large numbers so that they can be reused instead of getting garbage collected. The framework is based on static code analysis and code instrumentation. It takes in compiled code and so does not require access to source code of the application. As a case study, we passed publicly available applications through R3 to fine tune their performance. We compared energy, data and memory consumed by these applications before and after the code injection to corroborate our claims of improvement in performance. The data consumption reduced by a factor of 12.2 after removing advertisements, energy consumption reduced by a factor of 1.88 by optimizing the wake lock type and energy consumption reduced by a factor of 3.7 after optimizing GPS location update frequency. The pause times due to garbage collection reduced from 184 ms to 80 ms as the object pool size was increased from 0 to 1000.