To ensure the efficient operation of data centers today, a lot of electricity is spent. In 2013, only US data centers had about 91 billion kilowatt-hours of energy, which is equal to the annual output of 34 large coal-fired power plants.
Electricity remains one of the main cost items of data center companies, so they are trying to the efficiency of the computing infrastructure. For this, various technical solutions are used, some of which we will talk about today.
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virtualisation
When it comes to energy efficiency, virtualization has several undeniable advantages. First, consolidating existing services on fewer hardware servers saves on hardware maintenance, which means lower cooling, power, and floor space costs. Secondly, virtualization allows you to optimize the use of hardware resources and flexibly virtual power right in the process of work.
NRDC and Anthesis held a joint and found that replacing 3100 servers with 150 virtual hosts could reduce energy costs by $2,1 million per year. The organization that was the object of interest saved on the maintenance and purchase of equipment, reduced the staff of system administrators, received a guarantee of data recovery in case of any problems, and got rid of the need to build another data center.
According to the results Gartner, in 2016, the level of virtualization of many companies will exceed 75%, and the market itself will be valued at $5,6 billion. However, there are certain factors that hinder the ubiquity of virtualization. One of the main reasons remains the difficulty of βrebuildingβ data centers to a new operating model, since the costs of this often exceed the potential benefits.
Energy management systems
Such systems can improve the energy efficiency of the cooling system or reduce the energy consumption of IT equipment, which ultimately leads to cost minimization. In this case, a special , which monitors the activity of servers, consumption and cost of electricity, automatically redistributing the load and even turning off equipment.
One type of energy management software is data center infrastructure management (DCIM) systems, which are used to monitor, analyze and predict the energy efficiency of various equipment. Most DCIM tools are not used to directly monitor the power consumption of IT and other equipment, but many systems are equipped with PUE (Power usage effectiveness) calculators. According to Intel and Dell DCIM, these solutions 53% of IT managers.
Today, most hardware is already geared towards energy efficiency, but hardware purchases often focus more on upfront price or performance than total cost of ownership, leaving energy-efficient hardware behind. . In addition to reducing electricity bills, such equipment also the amount of CO2 emissions into the atmosphere.
Data Compression
There are also less obvious approaches to improve the energy efficiency of data centers, such as reducing the amount of stored data. Compression of infrequently used data save up to 30% of energy, even taking into account the fact that resources are also spent on compression and decompression. Data deduplication can show an even more attractive result - 40-50%. At the same time, it should be noted that the use of low-capacity storages for βcoldβ data also helps to reduce power consumption.
Disabling "zombie servers"
One of the problems leading to inefficient use of electricity in data centers is idle equipment. Experts that some companies cannot realistically estimate the required amount of resources, while the rest are purchasing server capacities with the expectation of the future. As a result, almost 30% of servers are idle, while consuming $30 billion of energy per year.
At the same time, according to the study, IT managers identify between 15 and 30% of installed servers, but do not write off the equipment for fear of possible consequences. Only 14% of respondents kept records of unused servers and knew their approximate number.
One of the solutions to this problem is the use of public clouds with a pay-as-you-go payment model, when the company pays only for the capacity that is actually used. Many companies are already operating under this scheme, and the owner of the Aligned Energy data center in Plano, Texas, claims that this allows customers to save from 30 to 50% per year.
Data center climate control
On the energy efficiency of the data center the microclimate of the room in which the equipment is located. For efficient operation of cooling plants, it is necessary to minimize cold losses by isolating the data center room from the external environment and preventing heat transfer through walls, ceiling and floor. An excellent way is a vapor barrier, which also regulates the level of humidity in the room.
Humidity that is too high can lead to various equipment malfunctions, increased wear and corrosion, while too low humidity can lead to electrostatic discharges. determines the optimal level of relative humidity for the data center in the range from 40 to 55%.
Efficient air flow distribution can also save 20-25% of electricity consumption. Proper placement of equipment racks will help with this: dividing the computer rooms of the data center into "cold" and "hot" corridors. At the same time, it is necessary to ensure the isolation of the corridors: install perforated plates in the necessary places and use blank panels between the rows of servers to prevent mixing of air flows.
It is also worth considering not only the location of the equipment, but also the location of the climate system. When dividing the hall into "cold" and "hot" aisles, air conditioners should be installed perpendicular to hot air flows to prevent the latter from penetrating into the aisle with cold air.
An equally important aspect of effective data center temperature management is the placement of wires, which can obstruct airflow, reducing static pressure and reducing the cooling efficiency of IT equipment. Correcting the situation will allow the movement of cable trays from under the raised floor closer to the ceiling.
Natural and liquid cooling
An excellent alternative to dedicated climate control systems is free cooling, which can be used during cold seasons. Today, technology makes it possible to switch to using an economizer when the weather permits. According to a study by Battelle Laboratories, free cooling reduces data center energy bills by 13%.
There are two types of economizers: those that use only dry air, and those that use additional irrigation when there is insufficient air cooling. Some systems can combine different types of economizers to form multi-level cooling systems.
But air-cooling systems are often inefficient due to the mixing of air flows or the inability to use the excess heat removed. In addition, the installation of such systems often entails additional costs for air filters and constant monitoring.
Many experts believe that liquid cooling does the job better. Representative of the Danish vendor Asetek, specializing in the creation of liquid cooling systems for servers, John Hamill, that liquid is about 4 times more efficient in terms of heat storage and transfer than air. And during an experiment conducted by Lawrence Berkeley National Laboratory in collaboration with American Power Conversion Corporation and the Silicon Valley Leadership Group, that due to the use of liquid cooling and the supply of water from the cooling tower, in some cases, energy savings reached 50%.
Other technologies
Today, there are three areas that will help make data centers more efficient: the use of multi-core processors, built-in cooling systems, and cooling at the chip level.
Computer manufacturers believe that multi-core processors, by completing more tasks in a shorter period, will reduce the energy consumption of servers by 40%. An example of the efficiency of an integrated cooling system is the CoolFrame solution from Egenera and Emerson Network Power. It takes the hot air coming out of the servers, cools it and "throws" it into the room, thereby reducing the load on the main system by 23%.
Concerning Chip cooling, it allows heat to be dissipated directly from server hotspots such as CPUs, GPUs, and memory modules to the ambient air in the rack or outside the machine room.
Increasing energy efficiency has become a real trend today, which is not surprising, given the volume of consumption of data centers: 25-40% of all operating expenses are accounted for by paying electricity bills. But the main problem is that every kilowatt-hour consumed by IT equipment is converted into heat, which is then removed using cooling equipment that requires a lot of energy. Therefore, in the coming years, reducing the energy consumption of data centers will not cease to be relevant - more and more new ways to improve the energy efficiency of data centers will appear.
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Source: habr.com