RUI/CSR-PDOS: Cooperative Prefetching for Mobile Devices

许多移动计算应用程序面临的一个基本挑战是数据管理。数据应该随时随地可用。然而，在跨个人设备集合（例如笔记本电脑、PDA和移动电话）管理用户的个人数据（例如，数据文件、电子邮件和缓存网页）方面，这项任务尤其难以支持。移动环境的两个特性使数据管理特别具有挑战性：网络断开和设备资源限制，特别是能源限制。这项工作的目标是提供个人数据的最大可用性和一致性，以及个人设备收集的最大总设备寿命。为了实现这一目标，该项目开发了一套协作预取算法，使设备能够在连接到信息源时检索相关数据。此外，该算法有效地分配了跨设备集合执行预取的能量负担。该评估研究了在笔记本电脑和ipaq集合上运行的算法的性能。考虑两个主要指标：设备的总生命周期和用户数据请求的命中率。这项工作的总体影响将是提高移动设备和应用程序的可用性，并最大化移动设备的使用寿命。此外，这个项目的学生参与者是来自美国最好的全女子本科院校之一的芒特霍利奥克学院的本科生。因此，该项目还将有助于提高妇女对系统研究的全面参与。

A fundamental challenge for many mobile computing applications is datamanagement. Data should be available anywhere at anytime. However,this task is particularly difficult to support with respect tomanaging a user's personal data (e.g., data files, email, and cachedweb pages) across a collection of personal devices (e.g., a laptop,PDA, and mobile phone). Two properties of the mobile environment makedata management particularly challenging: network disconnection anddevice resource constraints, particularly energy constraints. Thegoal of this work is to provide maximal availability and consistencyof personal data as well as maximal aggregate device lifetime for acollection of personal devices. To accomplish this goal, the projectdevelops a set of cooperative prefetching algorithms that enabledevices to retrieve relevant data when connected to the informationsource. Further, the algorithms efficiently distribute the energyburden of performing prefetching across the collection of devices.The evaluation investigates the performance of the algorithms in animplementation running on a collection of laptop computers and iPAQs.Two primary metrics are considered: the aggregate lifetime of thedevices and the hit rate of user requests for data. The overarchingimpacts of this work will be improved usability of mobile devices andapplications and maximization of mobile device lifetime. Further, thestudent participants in this project are undergraduate women fromMount Holyoke College, one of the nation's finest all-womenundergraduate institutions. Therefore, the project will also serve toimprove the overall participation of women in systems research.