Microsoft Taps Ampere’s Arm Chip to Power Azure Virtual Machines

Microsoft has announced that their Azure Virtual Machines powered by the Arm-based 80-core Ampere Altra processors are now generally available in over 10 Azure regions globally. 

Customers will be offered the Dps v5 and Dpsd v5 virtual machines for general computing, as well as the Eps v5 and Epsd v5 virtual machines that are optimized for memory-intensive computing. 

This will be the first time that Microsoft Azure has made Arm–based virtual machines available to their users. Aside from Arm Microsoft Windows 11 Pro and Enterprise, various flavors of Linux including Canonical Ubuntu, Red Hat Enterprise Linux, Debian, and CentOS will also be available. Additionally, the Azure Kubernetes Service will also provide access to Arm-based Kubernetes Clusters. 

 

The Ampere Altra processor has 80 Arm cores. Image used courtesy of Ampere

 

The company behind the processor, Ampere, was founded in 2018 and specializes in “cloud native” processors, focusing on a sustainable cloud computing model. The company claims that the Azure Virtual Machines being supported by the Ampere Altra perform 39% and 47% better than the equivalent Intel and AMD counterparts, respectively. In 2020, Ampere announced its 128-core processor, the Altra Max.

 

Features of the 80-Core Ampere Altra

Some notable features of the 80-core Ampere Altra processor:

• 80x Arm v8.2+ 64-bit CPU cores with processing speeds up to 3.30 GHz
• Caches
  • Per core: 64 KB L1 I-cache, 64KB L1 D-cache, and 1 MB L2 cache
  • System: 32 MB
  • Claims 100% predictable performance and elimination of “noisy neighbor problem”
• 2x 128-bit SIMD
• 8x 72-bit DDR4-3200 channel memory
• 128x PCIe Gen4 lanes
• Power:
  • Usage: 187 W
  • Thermal Design Power: 250 W
• Full interrupt (GICv3) and I/O (SMMUv3) virtualization

More information is available in the Ampere Altra datasheet.

 

Ampere Altra block diagram. Image used courtesy of Ampere. (Click image to enlarge)

 

Arm’s Advantage for Cloud-Based Processing

Cloud based computing and services have become quite ubiquitous in day-to-day life and critical for many businesses. A non-trivial number of services are now accessed via the cloud, whether that’s music/movie streaming, online banking, or personal data storage. 

This has left cloud service providers facing the challenge of continuing to provide ever increasing reliability and performance, while trying to minimize energy consumption, amount of hardware to maintain, real-estate required to host server centers, and of course cost to the customers it serves. 

While Intel and AMD will still have their place in the foreseeable future, Arm architecture is proving to be an interesting alternative that manages to provide performance on top of efficiency.

 

Is Arm simply more efficient by nature? 

The answer is a little complicated, and it really depends on who you ask and what metrics they are using to determine efficiency. 

Generally speaking, there are two explanations typically provided if we are concerned about energy consumption and performance. 

The first, is that RISC instruction sets (which Arm uses) require fewer clock cycles to perform the same instruction when compared to CISC (which Intel uses).

The second and possibly more relevant explanation is that Arm licenses its architecture, instead of fabricating its own processors. This means that licensees can incorporate an Arm processor more intentionally into their hardware designs to make it more optimized and efficient. 

 

What This Offering Means for Azure

While the Ampere Altra Virtual Machines are the first Arm virtual machines being offered by Microsoft Azure, this just means they are just catching up to their competition.

Amazon is already on its third generation of their in-house developed, Arm-based Graviton server processors, with the Gravitron3 having been announced late 2021. Some clear differences between Graviton3 and the Ampere Altra, is the former’s use of DDR5 and Gen5 PCIe. 

Ampere had also announced that their processors will be used in Google Cloud’s Tau2A virtual machines, with a preview in July 2022 and general availability expected in the next few months.

As of Q1 2022, Microsoft Azure has approximately 22% of the overall cloud services market share, only behind Amazon which is ahead at 33% market share. So even without Arm-based virtual machines, they have been doing quite well. 

 

As of Q1 2022, Microsoft had 22% of the Cloud Services market share, trailing just behind Amazon. Image used courtesy of Insider Intelligence

 

It’s not clear if offering Arm-based virtual machines will have a significant impact on Microsoft Azure’s standing in the cloud services market. However, the demand for Arm-based processing is expected to increase in the next decade, especially for server centers. It probably doesn’t hurt that Apple’s M1 and M2 processors are also Arm based.

Either way, Arm is trending up and Microsoft Azure’s adoption is a part of the trend.