【摘要】：隨著計(jì)算機(jī)技術(shù)和移動互聯(lián)網(wǎng)技術(shù)的迅速發(fā)展,嵌入式移動終端(例如手機(jī)、平板)已經(jīng)成為人們?nèi)粘Ｉ钪胁豢扇鄙俚囊徊糠�。嵌入式移動便攜設(shè)備依靠電池作為能量補(bǔ)給,而電池的容量卻受體積和重量的限制很難有效提高,因此嵌入式移動設(shè)備的功耗問題成為當(dāng)今研究的一個關(guān)鍵問題。 降低嵌入式系統(tǒng)的功耗有多種方法。其中動態(tài)電源管理(Dynamic Power Management, DPM)和動態(tài)電壓頻率調(diào)整技術(shù)(Dynamic Voltage and Frequency Scaling, DVFS)是降低系統(tǒng)功耗的兩種關(guān)鍵技術(shù)。本文從動態(tài)電源管理和動態(tài)電壓頻率調(diào)整技術(shù)兩種策略降低優(yōu)化移動嵌入式系統(tǒng)的功耗。 動態(tài)電源管理主要依據(jù)設(shè)備工作負(fù)載的變化切換其工作狀態(tài)以達(dá)到系統(tǒng)功耗最小化。例如當(dāng)外圍設(shè)備的空閑期足夠長時,使其關(guān)閉或進(jìn)入休眠狀態(tài)以節(jié)約電池電量。本文首先從應(yīng)用層、應(yīng)用框架層、Linux內(nèi)核層分析了Google Android的電源管理機(jī)制原理,然后從小流量模式(10Kb/分鐘)和大流量模式(2Mbit/分鐘)兩種情況實(shí)驗(yàn)并分析了Android網(wǎng)絡(luò)模塊在系統(tǒng)總功耗中的重要作用,接著在此基礎(chǔ)上提出了一個對Android網(wǎng)絡(luò)模塊的動態(tài)電源管理優(yōu)化解決方案。該方案從網(wǎng)絡(luò)流量、電池電量、時間、是否下班高峰階段四個因素考慮,實(shí)現(xiàn)Android系統(tǒng)在網(wǎng)絡(luò)模塊上的動態(tài)電源管理。由實(shí)驗(yàn)結(jié)果可以看出,手機(jī)移動網(wǎng)絡(luò)模塊(GPRS/WIFI)在手機(jī)系統(tǒng)功耗中占據(jù)了十分重要的位置,因此該解決方案對提高移動終端的能量利用率、降低移動終端的功耗具有重大的意義。 動態(tài)電壓頻率調(diào)整技術(shù)是降低嵌入式系統(tǒng)功耗的另一種重要方法。DVFS根據(jù)系統(tǒng)任務(wù)的緊迫程度來動態(tài)調(diào)節(jié)處理器的供電電壓和時鐘頻率,以達(dá)到任務(wù)響應(yīng)時間和系統(tǒng)功耗之間的平衡。嵌入式移動終端中使用的處理器通常都具備了動態(tài)電壓頻率調(diào)整能力,在操作系統(tǒng)中如何高效使用處理器提供的這一能力降低功耗成為一個值得研究的問題。本文針對以Linux為內(nèi)核的移動操作系統(tǒng),提出了一種優(yōu)化的、細(xì)粒度的DVFS算法,并在Android操作系統(tǒng)上加以實(shí)現(xiàn)。該算法基于歷史數(shù)據(jù),使用線性預(yù)測的方法,指導(dǎo)電壓頻率調(diào)整的方向和幅度,線性預(yù)測中的參數(shù)通過回歸方法確定。實(shí)驗(yàn)結(jié)果表明,本文所提的優(yōu)化細(xì)粒度DVFS算法相比于Linux內(nèi)核默認(rèn)使用的粗粒度調(diào)頻算法,能降低系統(tǒng)13.55%的功耗,提升了移動終端的續(xù)航時間。
[Abstract]:With the rapid development of computer technology and mobile Internet technology, embedded mobile terminals (such as mobile phones, tablets) have become an indispensable part of people's daily life. Embedded mobile portable devices rely on batteries as energy recharge, but the capacity of batteries is limited by volume and weight. Therefore, the power consumption of embedded mobile devices has become a key issue. There are many ways to reduce the power consumption of embedded systems. Dynamic power management (Dynamic Power Management, DPM) and dynamic voltage frequency adjustment (Dynamic Voltage and Frequency Scaling, DVFS) are two key technologies to reduce power consumption. In this paper, the power consumption of mobile embedded system is reduced by two strategies: dynamic power management and dynamic voltage frequency adjustment. Dynamic power management is mainly based on the variation of the device workload to switch the working state to minimize the power consumption of the system. For example, when a peripheral device has a long idle period, turn it off or go to sleep to save battery power. Firstly, this paper analyzes the principle of Google Android power management mechanism from the application layer and application frame layer. Then, the important role of Android network module in the total power consumption of the system is analyzed by two experiments: small traffic mode (10Kb/ minute) and large traffic mode (2Mbit/ minute). Then a dynamic power management optimization solution for Android network module is proposed. Considering four factors, such as network flow, battery power, time, whether or not the off-duty peak stage, this scheme realizes the dynamic power management of Android system on the network module. It can be seen from the experimental results that mobile network module (GPRS/WIFI) occupies a very important position in the power consumption of mobile phone system, so this solution has great significance to improve the energy utilization of mobile terminal and reduce the power consumption of mobile terminal. Dynamic voltage frequency adjustment is another important method to reduce the power consumption of embedded system. DVFS dynamically adjusts the power supply voltage and clock frequency of the processor according to the urgency of the system task. In order to achieve a balance between task response time and system power consumption. The processors used in embedded mobile terminals usually have the ability to adjust the dynamic voltage frequency. How to efficiently use the processor to reduce the power consumption in the operating system is a problem worth studying. In this paper, an optimized, fine-grained DVFS algorithm for mobile operating system with Linux kernel is proposed and implemented on Android operating system. Based on historical data, the method of linear prediction is used to guide the direction and amplitude of voltage frequency adjustment. The parameters of linear prediction are determined by regression method. The experimental results show that the proposed optimized fine-grained DVFS algorithm can reduce the power consumption of the system by 13.55% compared with the coarse-grained FM algorithm used by the Linux kernel by default and improve the mobile terminal life.
【學(xué)位授予單位】：北京交通大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2012
【分類號】：TP368.1

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相關(guān)博士學(xué)位論文 前1條

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本文編號：2157823