DOCSLIB.ORG

Page Program: Information Technology Engineering Curriculum Scheme

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Page Program: Information Technology Engineering Curriculum Scheme Program: _Information Technology_ Engineering Curriculum Scheme: Rev2016 Examination: Third Year Semester VI Course Code: _____ and Course Name: GREEN IT Time: 1 hour Max. Marks: 50 ===================================================================== For the students:- All the Questions are compulsory and carry equal marks . Q1. Climate Savers Computing Initiative was created by which technology leaders? Option A: Microsoft Option B: Intel and google Option C: Apple Option D: Vista Q2. Which set of standards addresses environmental management systems? Option A: ISO 9000 Option B: ISO 14000 Option C: ISO 26000 Option D: ISO 31000 Q3. Lead-acid batteries are most commonly a component of which piece of IT equipment? Option A: PC motherboards Option B: LCD monitors Option C: Notebook computers Option D: Uniterruptible Power supplies Q4. Power Usage Effectiveness is calculated by: Option A: Dividing energy used for the IT department by energy used for the entire organization Option B: Dividing energy used to maintain IT facilities by energy needed to power IT equipment Option C: Dividing energy needed to power IT equipment by total number of servers Option D: Multiplying energy used per hour by number of operating hours per year for the IT department Q5. Approximately what percentage of all toxic material found in landfills originates from electronic equipment? Option A: 10% Option B: 30% Option C: 50% Option D: 70% Q6. Which power state is also known as hibernate mode? Option A: S1 Option B: S2 Option C: S3 Option D: S4 1 | Page Q7. To properly control screen brightness levels, IT administrators should: Option A: Change settings using the monitor's control buttons Option B: Change settings using the Windows control panel Option C: Change settings within the BIOS Option D: Change settings using keyboard controls Q8. Programs such as SpeedStep and LongHaul are able to conserve energy by: Option A: Sending a computer to hibernate mode as soon as it becomes inactive Option B: Throttling CPU frequency on the fly Option C: Redirecting fans and cooling systems to the CPU Option D: Allowing a PC to operate while in a lower global power state Q9. Which standard regulates the use of Power Over Ethernet (PoE) technology? Option A: IEEE 802.11b Option B: IEEE 802.3 Option C: IEEE 802.15.1 Option D: IEEE 802.6 Q10. Which is NOT a benefit of passive heat-sink cooling when compared to active cooling? Option A: Diminished energy usage Option B: Lower cost of operation Option C: Less dust and dirt build-up Option D: Increased cooling speed Q11. Hot migration refers to: Option A: Transferring a virtual environment to a new server without powering servers down Option B: Transferring a virtual environment when the server's temperature becomes too high Option C: Powering down both servers to transfer a virtual environment Option D: Sharing remote usage between two servers Q12. Installing software on a centralized server and sending it to users as needed is called: Option A: Application sending Option B: Application swapping Option C: Application migration Option D: Application streaming Q13. Which of the following are drawbacks of virtualization? (select all that apply) Option A: High initial investment Option B: More complex administration Option C: Increased licensing costs Option D: Increased energy usage Q14. The EPA's product rating system that assesses the environmental impact of consumer and commercial products is called: Option A: Energy Score Option B: Energy Check 2 | Page Option C: Energy Star Option D: Energy Star Q15. Energy efficiency readings should be taken: Option A: At the same time of day each day Option B: On the same day each week Option C: One week each month Option D: At varying times of day and days of the week Q16. The focus of TCO started with which computer component? Option A: Keyboards Option B: Monitors Option C: Notebooks Option D: furniture Q17. Which ISO standard provides its own framework for assessing and comparing green building construction? Option A: 21931 Option B: 14001 Option C: 811 Option D: 7 Q18. Running multiple power sources to increase reliability and prevent significant downtime in the event of a power failure is known as: Option A: duplexing Option B: Redundancy Option C: Dual-lining Option D: twisting Q19. A measure of the amount of greenhouse gasses released not only in the manufacture of something, but also the delivery, travel by employees, and so on is: Option A: ROI Option B: TCO Option C: Carbon footprint Option D: Triple bottom line Q20. Which device allows a user to use only a single set of peripherals with more than one PC? Option A: Aisle Option B: P3 Option C: KVM Option D: HRV Q21. Power strips that can shut off all outlets when the PC associated with them is turned off are said to be: Option A: Metered Option B: Smart Option C: Conditioned 3 | Page Option D: asymmetric Q22. The Fraunhofer Institute for Environmental, Safety and Energy Technology found that an organization with 300 workstations can eliminated 148 tons of carbon dioxide emissions over five years by: Option A: using smart power strips Option B: implementing telecommuting Option C: Using KVM switches Option D: Switching to thin clients Q23. Which of the following offers the ability to dynamically alter CPU usage to instantly meet the needs of programs in use while minimizing or eliminating unneeded power usage? Option A: SlowDown Option B: SpeedStick Option C: LongRun Option D: Transient Q24. You want to alter screen brightness on a Windows 7 laptop. Beneath which section of the Control Panel will you find the Power Options applet? Option A: Hardware and Sound Option B: Clock, Language, and Region Option C: Appearance and Personalization Option D: System and Security Q25. Applying a magnetic field to wipe a hard drive is known as: Option A: rescinding Option B: degaussing Option C: razing Option D: eradicating 4 | Page .
Load more

Recommended publications
  • Approaches in Green Computing
    Special Issue - 2015 International Journal of Engineering Research & Technology (IJERT) ISSN: 2278-0181 NSRCL-2015 Conference Proceedings Approaches in Green Computing Reena Thomas Fedrina J Manjaly 3 rd BCA, Department of Computer Science 3 rd BCA , Department of Computer Science Carmel College Carmel College Mala, Thrissur Mala, Thrissur Abstract— In a 2008 article San Murugesan defined green computing as "the study and practice of designing, manufacturing, using, and disposing of computers, servers, and associated subsystems — such as monitors, printers, storage devices, and networking and communications systems — efficiently and effectively with minimal or no impact on the environment."Murugesan lays out four paths along which he believes the environmental effects of computing should be addressed:Green use, green disposal, green design, and green manufacturing. Green computing can also develop solutions that offer benefits by "aligning all IT processes and practices with the core principles of sustainability, which are to reduce, reuse, and recycle; and finding innovative ways to use IT in business processes to deliver sustainability benefits across the Figure 1: Green Computing Migration Framework enterprise and beyond". I. INTRODUCTION II. APPROACHES In 1992, the U.S. Environmental Protection Agency A. Product longevity launched Energy Star, a voluntary labeling program that is Gartner maintains that the PC manufacturing process designed to promote and recognize energy-efficiency in accounts for 70% of the natural resources used in the life monitors, climate control equipment, and other cycle of a PC. More recently, Fujitsu released a Life Cycle technologies. This resulted in the widespread adoption of Assessment (LCA) of a desktop that show that sleep mode among consumer electronics.
    [Show full text]
  • Low-Power Computing
    LOW-POWER COMPUTING Safa Alsalman a, Raihan ur Rasool b, Rizwan Mian c a King Faisal University, Alhsa, Saudi Arabia b Victoria University, Melbourne, Australia c Data++, Toronto, Canada Corresponding email: [email protected] Abstract With the abundance of mobile electronics, demand for Low-Power Computing is pressing more than ever. Achieving a reduction in power consumption requires gigantic efforts from electrical and electronic engineers, computer scientists and software developers. During the past decade, various techniques and methodologies for designing low-power solutions have been proposed. These methods are aimed at small mobile devices as well as large datacenters. There are techniques that consider design paradigms and techniques including run-time issues. This paper summarizes the main approaches adopted by the IT community to promote Low-power computing. Keywords: Computing, Energy-efficient, Low power, Power-efficiency. Introduction In the past two decades, technology has evolved rapidly affecting every aspect of our daily lives. The fact that we study, work, communicate and entertain ourselves using all different types of devices and gadgets is an evidence that technology is a revolutionary event in the human history. The technology is here to stay but with big responsibilities comes bigger challenges. As digital devices shrink in size and become more portable, power consumption and energy efficiency become a critical issue. On one end, circuits designed for portable devices must target increasing battery life. On the other end, the more complex high-end circuits available at data centers have to consider power costs, cooling requirements, and reliability issues. Low-power computing is the field dedicated to the design and manufacturing of low-power consumption circuits, programming power-aware software and applying techniques for power-efficiency [1][2].
    [Show full text]
  • Ernesto Sanchez, Giovanni Squillero, and Alberto Tonda Industrial
    Ernesto Sanchez, Giovanni Squillero, and Alberto Tonda Industrial Applications of Evolutionary Algorithms Intelligent Systems Reference Library, Volume 34 Editors-in-Chief Prof. Janusz Kacprzyk Prof. Lakhmi C. Jain Systems Research Institute University of South Australia Polish Academy of Sciences Adelaide ul. Newelska 6 Mawson Lakes Campus 01-447 Warsaw South Australia 5095 Poland Australia E-mail: [email protected] E-mail: [email protected] Further volumes of this series can be found on our homepage: springer.com Vol. 10. Andreas Tolk and Lakhmi C. Jain Vol. 23. Dawn E. Holmes and Lakhmi C. Jain (Eds.) Intelligence-Based Systems Engineering, 2011 Data Mining: Foundations and Intelligent Paradigms, 2011 ISBN 978-3-642-17930-3 ISBN 978-3-642-23165-0 Vol. 11. Samuli Niiranen and Andre Ribeiro (Eds.) Vol. 24. Dawn E. Holmes and Lakhmi C. Jain (Eds.) Information Processing and Biological Systems, 2011 Data Mining: Foundations and Intelligent Paradigms, 2011 ISBN 978-3-642-19620-1 ISBN 978-3-642-23240-4 Vol. 12. Florin Gorunescu Vol. 25. Dawn E. Holmes and Lakhmi C. Jain (Eds.) Data Mining, 2011 Data Mining: Foundations and Intelligent Paradigms, 2011 ISBN 978-3-642-19720-8 ISBN 978-3-642-23150-6 Vol. 13. Witold Pedrycz and Shyi-Ming Chen (Eds.) Granular Computing and Intelligent Systems, 2011 Vol. 26. Tauseef Gulrez and Aboul Ella Hassanien (Eds.) ISBN 978-3-642-19819-9 Advances in Robotics and Virtual Reality, 2011 ISBN 978-3-642-23362-3 Vol. 14. George A. Anastassiou and Oktay Duman Towards Intelligent Modeling: Statistical Approximation Vol. 27. Cristina Urdiales Theory, 2011 Collaborative Assistive Robot for Mobility Enhancement ISBN 978-3-642-19825-0 (CARMEN), 2011 ISBN 978-3-642-24901-3 Vol.
    [Show full text]
  • Energy Efficient Scheduling of Parallel Tasks on Multiprocessor Computers
    J Supercomput (2012) 60:223–247 DOI 10.1007/s11227-010-0416-0 Energy efficient scheduling of parallel tasks on multiprocessor computers Keqin Li Published online: 12 March 2010 © Springer Science+Business Media, LLC 2010 Abstract In this paper, scheduling parallel tasks on multiprocessor computers with dynamically variable voltage and speed are addressed as combinatorial optimiza- tion problems. Two problems are defined, namely, minimizing schedule length with energy consumption constraint and minimizing energy consumption with schedule length constraint. The first problem has applications in general multiprocessor and multicore processor computing systems where energy consumption is an important concern and in mobile computers where energy conservation is a main concern. The second problem has applications in real-time multiprocessing systems and environ- ments where timing constraint is a major requirement. Our scheduling problems are defined such that the energy-delay product is optimized by fixing one factor and minimizing the other. It is noticed that power-aware scheduling of parallel tasks has rarely been discussed before. Our investigation in this paper makes some initial at- tempt to energy-efficient scheduling of parallel tasks on multiprocessor computers with dynamic voltage and speed. Our scheduling problems contain three nontriv- ial subproblems, namely, system partitioning, task scheduling, and power supply- ing. Each subproblem should be solved efficiently, so that heuristic algorithms with overall good performance can be developed. The above decomposition of our op- timization problems into three subproblems makes design and analysis of heuristic algorithms tractable. A unique feature of our work is to compare the performance of our algorithms with optimal solutions analytically and validate our results experimen- tally, not to compare the performance of heuristic algorithms among themselves only experimentally.
    [Show full text]
  • Comptia Fc0-Gr1 Exam Questions & Answers
    COMPTIA FC0-GR1 EXAM QUESTIONS & ANSWERS Number : FC0-GR1 Passing Score : 800 Time Limit : 120 min File Version : 31.4 http://www.gratisexam.com/ COMPTIA FC0-GR1 EXAM QUESTIONS & ANSWERS Exam Name: CompTIA Strata Green IT Exam Visualexams QUESTION 1 A small business currently has a server room with a large cooling system that is appropriate for its size. The location of the server room is the top level of a building. The server room is filled with incandescent lighting that needs to continuously stay on for security purposes. Which of the following would be the MOST cost-effective way for the company to reduce the server rooms energy footprint? A. Replace all incandescent lighting with energy saving neon lighting. B. Set an auto-shutoff policy for all the lights in the room to reduce energy consumption after hours. C. Replace all incandescent lighting with energy saving fluorescent lighting. D. Consolidate server systems into a lower number of racks, centralizing airflow and cooling in the room. Correct Answer: C Section: (none) Explanation Explanation/Reference: QUESTION 2 Which of the following methods effectively removes data from a hard drive prior to disposal? (Select TWO). A. Use the remove hardware OS feature B. Formatting the hard drive C. Physical destruction D. Degauss the drive E. Overwriting data with 1s and 0s by utilizing software Correct Answer: CE Section: (none) Explanation Explanation/Reference: QUESTION 3 Which of the following terms is used when printing data on both the front and the back of paper? A. Scaling B. Copying C. Duplex D. Simplex Correct Answer: C Section: (none) Explanation Explanation/Reference: QUESTION 4 A user reports that their cell phone battery is dead and cannot hold a charge.
    [Show full text]
  • AMD's Early Processor Lines, up to the Hammer Family (Families K8
    AMD’s early processor lines, up to the Hammer Family (Families K8 - K10.5h) Dezső Sima October 2018 (Ver. 1.1) Sima Dezső, 2018 AMD’s early processor lines, up to the Hammer Family (Families K8 - K10.5h) • 1. Introduction to AMD’s processor families • 2. AMD’s 32-bit x86 families • 3. Migration of 32-bit ISAs and microarchitectures to 64-bit • 4. Overview of AMD’s K8 – K10.5 (Hammer-based) families • 5. The K8 (Hammer) family • 6. The K10 Barcelona family • 7. The K10.5 Shanghai family • 8. The K10.5 Istambul family • 9. The K10.5-based Magny-Course/Lisbon family • 10. References 1. Introduction to AMD’s processor families 1. Introduction to AMD’s processor families (1) 1. Introduction to AMD’s processor families AMD’s early x86 processor history [1] AMD’s own processors Second sourced processors 1. Introduction to AMD’s processor families (2) Evolution of AMD’s early processors [2] 1. Introduction to AMD’s processor families (3) Historical remarks 1) Beyond x86 processors AMD also designed and marketed two embedded processor families; • the 2900 family of bipolar, 4-bit slice microprocessors (1975-?) used in a number of processors, such as particular DEC 11 family models, and • the 29000 family (29K family) of CMOS, 32-bit embedded microcontrollers (1987-95). In late 1995 AMD cancelled their 29K family development and transferred the related design team to the firm’s K5 effort, in order to focus on x86 processors [3]. 2) Initially, AMD designed the Am386/486 processors that were clones of Intel’s processors.
    [Show full text]
  • ECE 571 – Advanced Microprocessor-Based Design Lecture 28
    ECE 571 { Advanced Microprocessor-Based Design Lecture 28 Vince Weaver http://web.eece.maine.edu/~vweaver [email protected] 9 November 2020 Announcements • HW#9 will be posted, read AMD Zen 3 Article • Remember, no class on Wednesday 1 When can we scale CPU down? • System idle • System memory or I/O bound • Poor multi-threaded code (spinning in spin locks) • Thermal emergency • User preference (want fans to run less) 2 Non-CPU power saving • RAM • GPU • Ethernet / Wireless • Disk • PCI • USB 3 GPU power saving • From Intel lesswatts.org ◦ Framebuffer Compression ◦ Backlight Control ◦ Minimized Vertical Blank Interrupts ◦ Auto Display Brightness • from LWN: http://lwn.net/Articles/318727/ ◦ Clock gating or reclocking ◦ Fewer memory accesses: compression. Simpler background image, lower power 4 ◦ Moving mouse: 15W. Blinking cursor: 2W ◦ Powering off unneeded output port, 0.5W ◦ LVDS (low-voltage digital signaling) interface, lower refresh rate, 0.5W (start getting artifacts) 5 More LCD • When LCD not powered, not twisted, light comes through • Active matrix display, transistor and capacitor at each pixel (which can often have 255 levels of brightness). Needs to be refreshed like memory. One row at a time usually. 6 Ethernet • PHY (transmitter) can take several watts • WOL can draw power when system is turned off • Gigabit draw 2W-4W more than 100Megabit 10 Gigabit 10-20W more than 100Megabit • Takes up to 2 seconds to re-negotiate speeds • Green Ethernet IEEE 802.3az 7 WLAN • power-save poll { go to sleep, have server queue up packets. latency • Auto association { how aggressively it searches for access points • RFKill switch • Unnecessary Bluetooth 8 Disks • SATA Aggressive Link Power Management { shuts down when no I/O for a while, save up to 1.5W • Filesystem atime • Disk power management (spin down) (lifetime of drive) • VM writeback { less power if queue up, but power failure potentially worse 9 Soundcards • Low-power mode 10 USB • autosuspend.
    [Show full text]
  • Redalyc.Optimization of Operating Systems Towards Green Computing
    International Journal of Combinatorial Optimization Problems and Informatics E-ISSN: 2007-1558 [email protected] International Journal of Combinatorial Optimization Problems and Informatics México Appasami, G; Suresh Joseph, K Optimization of Operating Systems towards Green Computing International Journal of Combinatorial Optimization Problems and Informatics, vol. 2, núm. 3, septiembre-diciembre, 2011, pp. 39-51 International Journal of Combinatorial Optimization Problems and Informatics Morelos, México Available in: http://www.redalyc.org/articulo.oa?id=265219635005 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative © International Journal of Combinatorial Optimization Problems and Informatics, Vol. 2, No. 3, Sep-Dec 2011, pp. 39-51, ISSN: 2007-1558. Optimization of Operating Systems towards Green Computing Appasami.G Assistant Professor, Department of CSE, Dr. Pauls Engineering College, Affiliated to Anna University – Chennai, Villupuram, Tamilnadu, India E-mail: [email protected] Suresh Joseph.K Assistant Professor, Department of computer science, Pondicherry University, Pondicherry, India E-mail: [email protected] Abstract. Green Computing is one of the emerging computing technology in the field of computer science engineering and technology to provide Green Information Technology (Green IT / GC). It is mainly used to protect environment, optimize energy consumption and keeps green environment. Green computing also refers to environmentally sustainable computing. In recent years, companies in the computer industry have come to realize that going green is in their best interest, both in terms of public relations and reduced costs.
    [Show full text]
  • Intel's Core 2 Family
    Intel’s Core 2 family - TOCK lines II Nehalem to Haswell Dezső Sima Vers. 3.11 August 2018 Contents • 1. Introduction • 2. The Core 2 line • 3. The Nehalem line • 4. The Sandy Bridge line • 5. The Haswell line • 6. The Skylake line • 7. The Kaby Lake line • 8. The Kaby Lake Refresh line • 9. The Coffee Lake line • 10. The Cannon Lake line 3. The Nehalem line 3.1 Introduction to the 1. generation Nehalem line • (Bloomfield) • 3.2 Major innovations of the 1. gen. Nehalem line 3.3 Major innovations of the 2. gen. Nehalem line • (Lynnfield) 3.1 Introduction to the 1. generation Nehalem line (Bloomfield) 3.1 Introduction to the 1. generation Nehalem line (Bloomfield) (1) 3.1 Introduction to the 1. generation Nehalem line (Bloomfield) Developed at Hillsboro, Oregon, at the site where the Pentium 4 was designed. Experiences with HT Nehalem became a multithreaded design. The design effort took about five years and required thousands of engineers (Ronak Singhal, lead architect of Nehalem) [37]. The 1. gen. Nehalem line targets DP servers, yet its first implementation appeared in the desktop segment (Core i7-9xx (Bloomfield)) 4C in 11/2008 1. gen. 2. gen. 3. gen. 4. gen. 5. gen. West- Core 2 Penryn Nehalem Sandy Ivy Haswell Broad- mere Bridge Bridge well New New New New New New New New Microarch. Process Microarchi. Microarch. Process Microarch. Process Process 45 nm 65 nm 45 nm 32 nm 32 nm 22 nm 22 nm 14 nm TOCK TICK TOCK TICK TOCK TICK TOCK TICK (2006) (2007) (2008) (2010) (2011) (2012) (2013) (2014) Figure : Intel’s Tick-Tock development model (Based on [1]) * 3.1 Introduction to the 1.
    [Show full text]
  • Green Computing
    International Journal of Modern Engineering Research (IJMER) www.ijmer.com Pp-63-69 ISSN: 2249-6645 Green Computing P. Visalakshi1, Soma Paul2, Mitra Mandal3 1Asst. Professor (S.G), Department of Computer Applications, SRM University, Kattankulathur 603202, Tamil Nadu, India 2Soma Paul, PG Student, Department of Computer Applications, SRMUniversity, Kattankulathur 603202, Tamil Nadu, India 3Mitra Mandal, Student, Department of Computer Applications, SRMUniversity, Kattankulathur 603202, Tamil Nadu, India ABSTRACT: Green Computing is a recent trend towards designing, building, and operating computer systems to be energy efficient. While programs such as Energy Star have been around since the early1990s, recent concerns regarding global climate change and the energy crisis have led to renewed interest in Green Computing. Data centers are significant consumers of energy – both to power the computers as well as to provide the necessary cooling. This paper proposes a new approach to reduce energy utilization in data centers. In particular, our approach relies on consolidating services dynamically onto a subset of the available servers and temporarily shutting down servers in order to conserve energy. We present initial work on a probabilistic service dispatch algorithm that aims at minimizing the number of running servers such that they suffice for meeting the quality of service required by service-level agreements. making the use of computers as energy-efficient as possible, and designing algorithms and systems for efficiency-related computer technologies. ORIGINS: In 1992, the U.S. Environmental Protection Agency launched Energy Star, a voluntary labeling program that is designed to promote and recognize energy-efficiency in monitors, climate control equipment, and other technologies.
    [Show full text]
  • ECE 571 – Advanced Microprocessor-Based Design Lecture 19
    ECE 571 { Advanced Microprocessor-Based Design Lecture 19 Vince Weaver http://www.eece.maine.edu/∼vweaver [email protected] 2 April 2013 Project/HW Reminder • Homework #4 was posted, due on Friday. • Hardware issues with x86. Procure machine? 1 Metrics Clarification • Energy delay = E*t (J*s), Energy delay squared = E*t*t (J*s*s), Smaller is better • In related papers it is confusing, as no one shows formula (despite academic papers loving formulas). Often they use the inverse (so larger is better?) which also confuses things • Other papers use MIPS/Watt = insn/J Not cross-platform. You really want to optimize for time, 2 not for instructions which can vary for lots of reasons and doesn't exactly equate to time. 3 DVFS and other CPU Power/Energy Saving Methods • A lot of related work • Will focus on actual implementations rather than academic papers this time 4 CMOS Energy Equation, Again 2 • Etot = [(CtotVddαf) + (NtotIleakageVdd)]t 5 Delay, Again CLVdd • Td = W µCox( L )(Vdd−Vt) 2 (Vdd−Vt) • Simplifies to fMAX ∼ Vdd • If you lower f, you can lower Vdd 6 DVFS • Voltage planes { on CMP might share voltage planes so have to scale multiple processors at a time • DC to DC converter, programmable. • Phase-Locked Loops. Orders of ms to change. Multiplier of some crystal frequency. • Senger et al ISCAS 2006 lists some alternatives. Two phase locked loops? High frequency loop and have programmable divider? 7 • Often takes time, on order of milliseconds, to switch frequency. Switching voltage can be done with less hassle. 8 When can we scale
    [Show full text]
  • ECE 571 – Advanced Microprocessor-Based Design Lecture 19
    ECE 571 { Advanced Microprocessor-Based Design Lecture 19 Vince Weaver http://web.eece.maine.edu/~vweaver [email protected] 10 April 2018 Announcements • HW#9 was posted, read DRAM measurement paper • Don't forget project update due Thursday ◦ Summary of your project ◦ How is it going? Still time to change if needed. ◦ Will you need any equipment from me? (Power measurement, accounts on machines) ◦ Related work. Three/Six references related to your work. Ideally academic papers, though websites also OK if you can't find any other reference. Always 1 supposed to do related work before starting project, people often do later. ◦ See the project handout for an example. 2 When can we scale CPU down? • System idle • System memory or I/O bound • Poor multi-threaded code (spinning in spin locks) • Thermal emergency • User preference (want fans to run less) 3 Non-CPU power saving • RAM • GPU • Ethernet / Wireless • Disk • PCI • USB 4 GPU power saving • From Intel lesswatts.org ◦ Framebuffer Compression ◦ Backlight Control ◦ Minimized Vertical Blank Interrupts ◦ Auto Display Brightness • from LWN: http://lwn.net/Articles/318727/ ◦ Clock gating or reclocking ◦ Fewer memory accesses: compression. Simpler background image, lower power 5 ◦ Moving mouse: 15W. Blinking cursor: 2W ◦ Powering off unneeded output port, 0.5W ◦ LVDS (low-voltage digital signaling) interface, lower refresh rate, 0.5W (start getting artifacts) 6 More LCD • When LCD not powered, not twisted, light comes through • Active matrix display, transistor and capacitor at each pixel (which can often have 255 levels of brightness). Needs to be refreshed like memory. One row at a time usually.
    [Show full text]