Literature Review
Student: 782920
Sustainable Computing Literature Review
Introduction
Cornell University ('What is Sustainable Computing?', n.d.) defines sustainable computing as ' ...a holistic approach that stretches from power to waste to purchasing to education and is a life-cycle management approach to the deployment of IT across an organization. The concept of Sustainable Computing considers total cost of ownership, the total impact, and the total benefit of technology systems.' This literature review focuses on power consumption in consumer electronic devices — specifically to understand where the power is being used the most, to understand how efficient smartphone batteries are and also any new technologies that are being developed to reduce power consumption.
Battery Consumption Analysis
Aaron Carroll & Gernot Heiser (2010, p.13) have shown that a regular user consumes 44% of their battery to GSM on a 3G smartphone, an additional 14% on graphics and 7% on backlight. Altogether this is 65% of the total battery being used on the display and network service itself. With the hardware changes in phones to accommodate 4G and also HD graphics, the battery consumption increases which leads smartphone manufacturers to increase the size and power of their batteries. This increase in power is only used to accommodate the additional consumption by the new hardware which has been implemented in the latest smartphones, leading to a more powerful but less efficient battery. The research is conclusive however there are limitations within this experiment, the first is the smartphone that has been used in the experiment is not one of the latest models which supports 4G technology - furthermore, the experiment was only conducted on one particular smartphone. The experiment could not be conducted with popular consumer models as it would not allow 'such a detailed analysis and breakdown of its power consumption'.
Power Saving Modes
New ways to make batteries more efficient are battery saving modes. The modes are: 'Power Saving Mode' and on Samsung devices there is an additional 'Ultra Power Saving Mode'. According to Samsung's support page, 'Galaxy Note 4- How to use and set up the power saving mode and ultra power saving mode?' (n.d., para 3), power saving mode saves the battery power by limiting the devices functions. Ultra Power Saving Mode extends standby time and reduces battery consumption by displaying a simpler layout and allowing limited access to applications. The new battery saving modes created by the smartphone manufacturers have a positive impact as it allows the consumer to limit the functions of the phone in order to preserve battery however it must be questioned whether these new functions work as well as they are claimed.
Cloud Computing
Peter Mell and Timothy Grace (2011, p.3) define cloud computing as '...a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction.' As cloud computing requires minimal management effort or service provider interaction it has become the future for technology systems - in relevance to smartphones: Antti P. Miettnen & Jukka K. Nurminen (2010, p.1) state that 'Cloud computing has the potential to save mobile client energy but the savings from offloading the computation need to exceed the energy cost of the additional communication'.
Anton, B., Jemal, A., & Rajkumar, B. (2012, p.755) state that data centers that hold Cloud applications consume large amounts of electrical energy which causes high operational costs and also a high carbon footprint. This leads on to green cloud computing where operational costs are decreased at the same time as the carbon footprint. With rising energy costs companies will have to find a solution to decrease the high operational costs as profits will decrease. Anton, B., et al. (2012, p.756) also state that there's ' ...increasing pressure from governments worldwide aimed at the reduction of carbon footprints, which have a significant impact on the climate change.' This can be seen as detrimental because companies may not see any profit emerging from cloud computing however it's more likely to be favourable as this area has so much potential.
Rachana, H., & Vijayalakshmi, R. P. (2015, February, p.439-440) have found 10 different ways of saving energy which are: resource virtualization, enabling energy; efficiently using resources; automation software, maximizing consolidation; pay-per-use and self-service, encouraging more efficient behavior and life-cycle management; reducing CPU power dissipation; using advance clock gating; using split plane power; using energy-efficient processors & reducing cooling requirements. A combination of all these techniques will allow cloud computing to run in an efficient and profitable manner. Consumers will have the option of using this service when they require it furthermore, this energy saving will allow cellular devices using cloud computing to have longer battery lives. Rachana, H., & Vijayalakshmi, R. P. (2015, February, p.440) state in the conclusion that green cloud computing is the future technology however the environmental factors must never be overlooked because '...the day will not be far when pros of cloud become cons for environment.'
Conclusion
From Aaron Carroll & Gernot Heiser (2010, p.13) we have discovered that 65% of a phones battery is used for GSM and display. The research is quite conclusive however due to the experiment conducted on only one particular model it cannot be verified whether 65% is correct for most consumer smartphones. In addition, this experiment was conducted before the introduction of 4G and HD screens on newer consumer smartphones. With the introduction of new hardware it can be assumed that the new technology will consume a larger percentage of the battery. New ideas have been brought about such as 'Power Saving Mode' and Samsungs 'Ultra Power Saving Mode' where consumers are given the option of making their batteries last longer by restricting applications from sending and receiving data and also having a more basic display — this does seem to work however official research has not taken place to verify how effective these modes are. Cloud Computing is the next step for power saving on smartphones, Antti P. Miettnen & Jukka K. Nurminen (2010, p.1) have stated that Cloud Computing has the potential to save mobile clients energy, however as Anton, B., et al. (2012, p.754) have stated data centers consume large amounts of electrical energy which causes high costs and a large carbon footprint. Rachana, H., & Vijayalakshmi, R. P. (2015, February, p.439-440) have found ways to decrease energy consumption — therefore reducing costs — and this leads to a more reliable Green Cloud Computing network, however it is clear more research and implementation is required on this subject.
Reference:
Aaron, C., & Gernot, H., (2010). An Analysis of Power Consumption in a Smartphone. Retrieved from: https://www.usenix.org/legacy/event/usenix10/tech/full_papers/Carroll.pdf
Anton, B., Jemal, A., & Rajkumar, B. (2012). Energy-aware resource allocation heuristics for efficient management of data centers for Cloud computing. Future Generation Computer Systems, 28. Retrieved from: http://www.researchgate.net/profile/Jemal_Abawajy/publication/235720422_Energy-Aware_Resource_Allocation_Heuristics_for_Efficient_Management_of_Data_Centers_for_Cloud_Computing/links/0f3175375b80a9d2bc000000.pdf
Antti, P. M., & Jukka, K. N. (2010). Energy efficiency of mobile clients in cloud computing. Retrieved from: https://www.usenix.org/legacy/events/hotcloud10/tech/full_papers/Miettinen.pdf
Galaxy Note 4- How to use and set up the power saving mode and ultra power saving mode?. (n.d.). Retrieved from: http://www.samsung.com/levant/support/skp/faq/1066589
Peter, M. & Timothy, G. (2011). The NIST definition of Cloud Computing. Retrieved from: http://faculty.winthrop.edu/domanm/csci411/Handouts/NIST.pdf
Rachana, H., & Vijayalakshmi, R. P. (2015, February). Green Cloud Computing. IJETSR, 4(3). Retrieved from: http://ijsetr.com/uploads/154236IJSETR4010-82.pdf
What is Sustainable Computing?. (n.d.) Retrieved from: https://computing.fs.cornell.edu/Sustainable/fsit_definition.cfm