Servers can consume more than half of the energy in modern data centers, which makes server efficiency attractive to companies looking to hit carbon-neutral sustainability targets. Plus, reducing energy usage can save money.
To help reach that goal, here are five ways to boost server efficiency, according to recent research from the Uptime Institute, which is focused on improving the performance, efficiency, and reliability of business-critical infrastructure.
- Upgrade to a newer server generation. For decades, server energy efficiency has consistently improved thanks to improved efficiency of processors that power them.
- Pick servers with high compute capacity as measured in number of transactions per second. Those are the most energy efficient.
- Go for high core count. In general, efficiency improves with the number of cores, although there is some tapering off at the highest end.
- Be aware that while a server can be more energy efficient, its actual overall power consumed (Watts) can increase even as its efficiency (transactions per second per Watt) increases.
- Embrace power-management features in two ways: by reducing core CPU voltage and frequency as utilization increases, and by moving unneeded cores to idle state.
For its analysis, Uptime focused servers that use AMD EPYC or Intel Xeon processors, and it examined server generations from 2017, 2019, and 2021 using data from The Green Grid’s SERT database (additional details on the SERT data can be found at the end of the article).
Get rid of old, power-sucking servers
Older servers are less energy efficient than new ones, says Jay Dietrich, Uptime Institute’s research director of sustainability. For example, Intel servers’ efficiency improved by 34% between 2017 and 2019 for CPUs running at 50% utilization, according to a recent report he co-authored. And AMD-based servers saw a whopping 140% improvement, he says.
Upgrading from 2019 to 2021 CPU-based servers will increase efficiency by 32% for Intel servers, and by 47% for AMD servers. The improved efficiency numbers cut across all levels of utilization.
When comparing AMD and Intel servers, Intel servers were more efficient in 2017 at all levels of CPU utilization, but since 2019 AMD has leapt ahead. With 2021 servers running at 50% utilization, the average AMD server is 74% more efficient than an Intel.
Don’t underuse servers
Just like a car idling in traffic, servers that aren’t running at full capacity are just wasting energy.
According to a 2022 Uptime Institute data-center survey, only 47% of companies got 50% or better server utilization, up from 36% in 2020. Those numbers might be inflated some because companies that responded may have reported just their best-performing servers—for example those only running batch jobs, which might push utilization as high as 80%, Dietrich says.
Utilization rates in general, though, would likely be lower because many applications don’t run consistently. Business and enterprise software, for example, are used heavily during working hours but much less after hours. The utilization of servers can be increased by having the ones hosting business apps run less time-sensitive workloads during off-peak hours.
The effort is worth it. Doubling low CPU utilization (20% to 30%) to higher levels of (40% to 60%) can boost average efficiency dramatically, Uptime says.
For maximum impact, companies should look at increasing utilization while also upgrading servers to the latest models. According to Uptime, combining increased utilization with a server refresh, efficiency can more than double. That means an increase of 100% or…
