A few lines of Linux code could cut data centre emissions by 30%, academics claim
"It’s like rearranging the pipeline at a manufacturing plant so you don’t have people running around all the time.”
Data centres account for up to 4% of the total daily energy use of large economies, and that share of output is only likely to grow if AI demand continues to surge.
Now academics have claimed that a simple tweak to Linux kernel code could cut facilities' energy use by as much as 30%.
The technique is called "interrupt request suspension" and balances CPU power usage with efficient data processing.
By reducing unnecessary interruptions during high-traffic periods, it enhances network performance while maintaining low latency during quieter times.
Overall, computing accounts for roughly 5% of the world’s total energy use, with data centres accounting for 1% of that amount globally.
"That type of energy consumption is expected to significantly increase as computing power is needed to meet the exponential growth of artificial intelligence," the University said in a statement.
"Nearly all web traffic is routed through data centres, the majority of which use the open-source operating system Linux."
Could a small tweak power a giant leap for sustainability?
Computer science professor Martin Karsten and his co-author, Computer Science grad student Peter Cai, found data centres were inefficiently processing network traffic and devised a small change which made a major improvement.
“Information arrives at data centres in ‘packets,’ and then the data centre’s frontend, kind of like a receptionist at a front desk, figures out where to send those packets,” Karsten said.
“We didn’t add anything. We just rearranged what is done when - which leads to a much better usage of the data centre’s CPU caches. It’s kind of like rearranging the pipeline at a manufacturing plant, so that you don’t have people running around all the time.”
Karsten teamed up with Joe Damato, a distinguished engineer at Fastly, to develop a small section of code approximately 30 lines long that would improve Linux’s network traffic processing.
He claimed the new method could reduce the energy consumption of important data centre operations by as much as 30%.
“There is a long way to go yet"
The solution has now been tested, submitted to Linux for consideration and was published this month as part of Linux’s newest kernel, release version 6.13.
“All these big companies – Amazon, Google, Meta – use Linux in some capacity, but they’re very picky about how they decide to use it,” Karsten continued. “If they choose to ‘switch on’ our method in their data centres, it could save gigawatt hours of energy worldwide.
"Almost every single service request that happens on the Internet could be positively affected by this. We all have a part to play in building a greener future."
Karsten and Damato's Linux kernel code addition was based on research published in ACM SIGMETRICS Performance Evaluation Review.
Aoife Foley, IEEE senior member and professor in the School of Mechanical and Aerospace Engineering, Queen’s University Belfast, explained that the data centre Linux tweak was not the only answer to the problem.
“There is a long way to go yet," he said. "These facilities represent huge electricity demands, adding pressure to electricity grids and increasing the challenge of energy transitions, especially in smaller countries.
"Although it is impossible to calculate precisely, the entire ICT sector is estimated to account for about 1.4 per cent of CO2 emissions globally. Infrastructure and operations leaders have a responsibility here and need to consider the unnecessary waste associated with data storage and commit to generating power from more renewable sources.
“Modern enterprises continuously generate and accumulate vast amounts of data. This includes routine activities across enterprise systems, machines, sensors, and demand-side digitalisation. All of this data comes in multiple forms – whether redundant or critical. However, the majority is unstructured and inert content, commonly referred to as ‘dark data’ which is becoming more prevalent. The result is a large volume of digital data that needs to be stored, most of which will not even be accessed later.
“Those managing data centres and server rooms must strive for a high standard of energy efficiency, demonstrated through aggressive power use effectiveness (PUE) targets. Achieving sustainability means addressing environmental considerations during solution design as well as during the build. Solutions must meet pre-defined and agreed environmental sustainability criteria. This includes filtering dark data, removing unnecessary information from storage and relying upon ‘greener’ energy sources.”
Have you got a story or insights to share? Get in touch and let us know.
