Microsoft uses boiling liquid to cool servers in data centers
The data processed by Microsoft’s servers literally boils liquid inside a steel tank filled with servers. This is how you can describe the unusual submersible (immersion) liquid cooling system used in the company’s data center on the Columbia River’s east bank near Quincy, USA.
Unlike water, the liquid inside the tank is completely harmless to electronic components. Besides, its boiling point is only 50 degrees Celsius. This cooling effectively removes heat from the processors, allowing the servers to run at full capacity continuously without the risk of overheating. Inside the tank, steam rising from the boiling liquid contacts the cooled surface in the tank lid, as a result of which it condenses (turns into liquid) and returns to the servers, forming a closed cooling system.
Husam Alissa, the chief hardware engineer at Microsoft’s cutting-edge data center team, says the company is the first cloud service provider to adopt two-phase immersion cooling. Its implementation is Microsoft’s next step in meeting the demand for faster, more powerful data center computers at a time when the development of air-cooled systems has slowed.
Previously, processors were developed according to Moore’s Law, which stated that computer processors’ performance would approximately double every two years without increasing power consumption. Now the pace of this development began to slow down because the transistors’ size approached the minimum limit. Meanwhile, the demand for high-performance chips is growing. To provide the required level of performance, chipmakers have turned to more power-hungry architectures. The increased heating of such chips, in turn, raised the bar for cooling systems.
Microsoft notes that heat dissipation in liquids outweighs air cooling capabilities by several orders of magnitude. According to the company, using two-phase immersion cooling will increase data center performance following Moore’s Law in the coming years. And here, we add that not only Microsoft is actively developing the direction of immersion cooling of servers.
Microsoft sees a great future with submersible tank servers. The company says that in the event of a low equipment failure rate, it could move to a model in which components are not immediately replaced in the event of failure. This will limit vapor loss and allow tanks to be placed in hard-to-reach and remote locations. What’s more, the ability to tightly place servers in a tank allows for a rethinking of server architecture optimized for high-performance, low-latency applications as well as low operating costs. Such a reservoir, for example, could be placed under a 5G cell tower in a city center to serve self-driving cars. Microsoft currently has one capacity that runs workloads in a hyperscale data center.
