International News
In an era of exciting advances in data centre design , Microsoft ’ s reach seeks to extend the frontiers of computing , with major implications for the broader industry . Thus far , these initiatives have yet to be deployed at scale . But Microsoft ’ s focus on liquid cooling is being driven by changes in hardware that command a response .
The rise of artificial intelligence ( AI ), and the hardware that supports it , is reshaping the data centre industry ’ s relationship with servers . New hardware for AI workloads is packing more computing power into each piece of equipment , boosting the power density – the amount of electricity used by servers and storage in a rack or cabinet – and the accompanying heat . The trend is challenging traditional practices in data centre cooling , and prompting data centre operators to adapt new strategies to support high-density racks .
MORE SERVER-POWER REQUIRES MORE COOLING Russinovich further noted the heat generated by powerful new hardware like the NVIDIA A100 GPU chips , which feature prominently in new Azure Cloud offerings .
“ The A100 really represent a kind of trend that we ’ ve been seeing that ultimately results in more and more power consumption per server ,” he said . He also noted that general purpose chips were also featuring more cores , and thus drawing more power .
He said Microsoft has experimented with several approaches to liquid cooling , including a cold plate design , which typically contains a tubing system filled with liquid refrigerant . Russinovich tested cold plates using a personal gaming system , but said this approach would be hard to scale .
“ That is a great way to cool , but it ’ s got the downside that every single server has to be custom fitted for the pipes and the cold plates ,” he said . “ It ’ s not a one size fits all model .”
He cited similar challenges with a single-phase immersion cooling system in which liquid coolant is introduced into the server chassis .
That ’ s why Microsoft is now focused on two-phase immersion cooling , in which servers are immersed in a coolant fluid that boils off as the chips generate heat , removing the heat as it changes from liquid to vapour . The vapor then condenses into liquid for reuse , all without a pump . Data centre designs for this “ phase change ” cooling were pioneered by 3M as a use case for its Novec engineered fluid , which has a low boiling point .
BITCOIN TECH COMES TO HYPER-SCALE The video from Ignite showed a two-phase immersion system operating in Microsoft ’ s liquid cooling lab . The servers were enclosed in a system from Allied Control , which has been a pioneer in adapting extreme density cooling systems using Novec ( which is not named as the coolant in the Microsoft video , although 3M-branded boxes are visible in the background indicating their product used ).
In 2014 it created a high-density immersion cooling system that allowed its client to deploy a bitcoin mining operation on the upper floors of a skyscraper in Hong Kong .
The company was then acquired by bitcoin specialist Bitfury , which brought the technology to scale in containers filled with immersion tanks , which it used to create a 40-megawatt facility that l features power densities of 250kW per enclosure .
That disruptive potential is why the Open Compute Project has been working to enable wider adoption of liquid cooling , citing demand from hyper-scale computing providers , as well as new applications in edge computing . Microsoft has been among the participants in the OCP liquid cooling initiatives , which followed Google ’ s revelation that it has shifted to liquid cooling with its latest hardware for artificial intelligence .
Microsoft signalled its growing interest in liquid cooling initially in a blog post last year on its OCP initiatives .
“ While liquid cooling is a technology that has been used in specific use cases , such as bitcoin mining , we are not only investing in the solutions and technologies that will power new architectures , but also focusing intensely on the challenges that will come into play as we look to extend the reach of these capabilities to a hyper-scale cloud ,” the company wrote . RACA
QUOTE OF THE MONTH
“ Normal people believe that if it ain ’ t broke , don ’ t fix it . Engineers believe that if it ain ’ t broke , it doesn ’ t have enough features yet .”
– Scott Adams
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RACA Journal I May 2021 www . hvacronline . co . za