Computational Thinking - Учебное пособие (1176923), страница 13
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In recent years, Microsoftand other major companies, hosting online services, need touse more and more energy for their centers. The Microsoftfacility, which consumes up to 27 megawatts of energy at anygiven time, has built data centers in Washington to takeadvantage of the hydroelectric power produced by two damsin the region. Google’s data centers use half the industry’saverage amount of power.Nowadays as the companies are brainstorming solutions to cutcosts and increase revenue green computing takes a muchmore holistic approach than before.
The proposed andexisting strategies now range from the practical to the fanciful,and include government regulations, industry initiatives,environmentally friendly computers made of recyclablematerials.71In 2007 a global consortium of computer companies,including AMD, Dell, IBM, Sun Microsystems, and VMware, organized The Green Grid with the goal of improvingenergy efficiency in data centers and business computingsystems. To achieve the goal, The Green Grid collaborateswith individual companies, government agencies, and industrygroups to provide recommendations on best practices,metrics, and technologies that will improve data centers’energy efficiency.Since 2007 Dell has been accelerating its programs to reducehazardous substances in its computers, and its new OptiPlexdesktops are 50% more energy-efficient than similar systemsmanufactured before, thanks to more energy-efficientprocessors, new power management features, and otherfactors.
Microsoft, Google, Yahoo, Japanese Jujitsu have beenexpressing the environmental concerns about their datacenters’ carbon footprint and the measure of theenvironmental impact of an individual or organization’slifestyle. Google, Inc. states its improved energy usage andattributes this to the cooling technologies, such as ultraefficient evaporative cooling.
“Our carbon footprint iscalculated globally and includes our direct fuel use, purchasedelectricity, and business travel - as well as estimates foremployee commuting, construction, and server manufacturingat our facilities around the world”, says Google’s director ofenergy strategy Bill Weihl. With the aid of a self-styled ultraefficient evaporative cooling technology, Google has beenable to reduce its energy consumption to 50% of that of theindustry average.In 2010, the American Recovery and Reinvestment Act(ARRA) was signed into legislation by President Obama. Thebill allocated over $90 billion to be invested in greeninitiatives (renewable energy, smart grids, energy efficiency,etc.).Green computing today is a multifaceted, global effort toreduce consumption and provide sustainability.
The list of theparticipating countries is expanding including at the moment72the USA, China, Japan, India, Italy, Spain, Great Britain andRussia. Russia’s ongoing effort to raise its investments in highperformance computers to fuel the growth of its economythrough energy efficiency and sustainable technology isnoteworthy.Degree and postgraduate programs provide training in a rangeof information technology concentrations along withsustainable strategies in an effort to educate students how tocreate systems reducing its negative impact on theenvironment.
In the UK, Leeds Metropolitan Universityoffers an MSc Green Computing program in both full andpart-time access modes. The Australian National Universityoffers “ICT Sustainability” course as part of its informationtechnology and engineering masters programs.In 2012 the Russian Institute of Information Technology andTelecommunication SKFU in Stavropol won a grant of theBritish University of Newcastle for the development ofcurricula and programs graduate, postgraduateandprofessional development courses in “Eco-friendly computertechnology and communication” (Fostering innovations onGreen Computing - GREENCO).
The consortium of theproject consists of seven universities in Russia, six Ukrainianuniversities, and four educational institutions of the EuropeanUnion, including the University of Leads (UK), Institute ofScience and Technology information (Italy), SlovakianUniversity and the University of Loannina (Greece).There have been a number of International Conferences(including Slovak Second Workshop in May 2013 andBelgorod Third International Workshop in November 2013)devoted to Green and Safe Computing. The main goal of theprogram of international cooperation - the integration ofmodern developments in the field of information andtelecommunications in the learning process, taking intoaccount the impact of these developments on theenvironment, that is, adding ecological component in thetraining of IT professionals and the creation of the trainingcourses, which would preclude the negative impact on nature.73At the workshops some adjustments regarding greencomputing and IT support were discussed.
They include:algorithmic efficiency, computer virtualization, terminalservers, operating system support, product longevity, materialrecycling, telecommuting, and others.The efficiency of algorithms has an impact on the amount ofcomputer resources required for any given computing functionand there are many efficiency trade-offs in writing programs.Algorithm changes, such as switching from a slow (e.g. linear)search algorithm to a fast (e.g.
hashed or indexed) searchalgorithm can reduce resource usage for a given task fromsubstantial to close to zero. Algorithms can be used to routedata to the data centers where electricity is less expensive.Larger server centers are sometimes located where energy andland are inexpensive and readily available. Local availability ofrenewable energy, climate that allows outside air to be usedfor cooling, or locating them where the heat they producemay be used for other purposes could be factors in greensiting decisions.The approaches to actual reduction of network devices energyconsumption by proper network management techniques werealso surveyed in.
They were grouped into 4 main strategies:Adaptive Link Rate (ALR), Interface Proxying, Energy AwareInfrastructure, and Energy Aware Applications.Computer virtualization refers to the abstraction of computerresources, such as the process of running two or more logicalcomputer systems on one set of physical hardware. Withvirtualization, a system administrator could combine severalphysical systems into virtual machines on one single, powerfulsystem, thereby unplugging the original hardware andreducing power and cooling consumption. Virtualization canassist in distributing work so that servers are either busy or putin a low-power sleep state. In order to facilitate virtualcomputing several commercial companies and open-sourceprojects now offer software packages to enable virtualizationenhancements to the x86 instruction set into each of theirCPU product lines.74Terminal servers have also been used in green computing.When using the system, users at a terminal connect to acentral server, on which computing is done.
This can becombined with thin clients, which use up to1/8 amount ofenergy of a normal workstation, resulting in a decrease ofenergy costs and consumption. There has been an increase inusing terminal services with thin clients to create virtual labs.Examples of terminal server software include TerminalServices for Windows and the Linux Terminal Server Project(LTSP) for the Linux operating system.The dominant desktop operating system, Microsoft Windows,has included limited PC power management features sinceWindows 95.
Windows 2000 was the first NT-based operatingsystem to include power management. This required majorchanges to the underlying operating system architecture and anew hardware driver model. The power management systemwas significantly improved in Windows Vista to allow basicconfiguration by Group Policy. The most recent release,Windows 7 includes refinements for more efficient user ofoperating system timers, processor power management, anddisplay panel brightness. The most significant change inWindows 7 is in the user experience. The prominence of thedefault High Performance power plan has been reduced withthe aim of encouraging users to save power. Most productsoffer Active Directory integration and per-user/per-machinesettings with the more advanced offering multiple powerplans, scheduled power plans, anti-insomnia features andenterprise power usage reporting.Product longevity.According to the company Gartneranalysts the PC manufacturing process accounts for 70% ofthe natural resources used in the life cycle of a PC.
Anotherreport from Gartner recommends looking for productlongevity,includingupgradabilityandmodularity.Manufacturing a new PC makes a far bigger ecologicalfootprint than upgrading an existing one.Materials recycling. Recycling computing equipment can keepharmful materials as lead, mercury, and hexavalent chromium75out of landfills, and can also replace equipment, savingfurther energy and emissions.
Additionally, parts fromoutdated systems may be salvaged and recycled throughcertain retail outlets and municipal or private recyclingcenters. Computing supplies, such as printer cartridges, paper,and batteries may be recycled as well.Though the collection rate of e-waste is still very low even inthe most ecology-responsible countries like France, still thereare some first steps in this direction.Hewlett-Packard recently unveiled what it calls “the greenestcomputer ever” – the rp557000 desktop PC. The rp5700 hasan expected life of at least five years, and 90% of its materialsare recyclable. The computer is easy to disassemble and meetsthe European Union’s RoHS standards for the restriction ofthe use of certain hazardous substances in electrical andelectronic equipment.
Moreover, 24% of the rp5700’spackaging materials are made of recycled material.A drawback to many of these schemes is that computersgathered through recycling drives are often shipped todeveloping countries where environmental standards are lessstrict than in North America and Europe.Telecommuting.Ingreencomputinginitiativesteleconferencing and telepresence technologies are oftenimplemented. There are many advantages: increased workersatisfaction, reduction of greenhouse gas emissions, related totravel, and increased profit margins as a result of loweroverhead costs for office space, heat, lighting, etc. Many typesof jobs, such as sales, consulting, and field service integratewell with this technique.“We have just started to address the issue of greencomputing”, writes Andy Hopper in his paper “Computingfor the Future of the Planet”.
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