現代人使用智慧型手機時，有30%以上的時間是花費在玩手機遊戲。據統計，手機遊戲消耗了大部分的手機電量。為解決此議題，現有的電源管理多是針對中央處理器(CPU)進行頻率調整來省電。然而，現在的智慧型手機多利用GPU來輔助CPU進行遊戲的複雜運算。本篇論文提出一個能夠在盡可能不傷害使用者的遊戲體驗下動態調整CPU與GPU頻率用以省電的演算法。本方法於遊戲過程中分析遊戲所需要的服務品質與計算資源用量，進行即時頻率調整。為了能貼近使用者進行遊戲的環境，本篇論文將演算法實做於Google Nexus 7 平板電腦上，並測試不同種類遊戲的省電效果，而根據實驗結果，我們所提出的方法可以節省20%的系統耗電量。

Energy efficiency is a critical issue for battery-driven mobile
devices. With the increasing needs of graphic mobile games
on such devices, an on-line power governor for both CPUs
and GPUs is highly motivated. This study proposes an
adaptive on-line CPU-GPU governor of games on mobile
devices to reduce the energy. In contrast to existing governors,
an adaptive frequency scaling framework is presented
to switch the performance-driven or energy-driven to minimize
the energy without user attention. Also, to adjust the
dynamic of quality during game stages, an on-line learning
is applied to our framework to predict the required quality
and to sense the relations between quality and CPU/GPU
frequencies. The idea is implemented on Google Nexus 7
and evaluated with real-world gaming apps. The results
show that we can save up to 20% system energy (included
the network, screen, and systemidle power) for a high frame
rate game and maintaining a stable user experience.

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