Revolutionizing Cloud Servers: The Rise of SR-IOV Virtualization Technology

The Emergence of SR-IOV in Cloud Data Centers

Traditionally, servers were acquired and maintained for a specific purpose, necessitating upgrades to the server, RAM and storage as requirements evolved. This process often resulted in delays, high costs and downtime, highlighting a need for improvement.

Single Root I/O Virtualization (SR-IOV) completely revolutionizes the entire approach used in data centers to be more customer focused, agile and price competitive. 

Let’s Examine the Role of SR-IOV in Enhancing Cloud Data Centers

SR-IOV gained significant attention in 2015 when PCISIG^® incorporated it in their specifications. The Cloud Server industry adopted SR-IOV to serve as the primary data pathways for Virtual Machines (VMs) to communicate with their dedicated namespace segments on NVMe^® SSDs. Since then, an increasing number of vendors have incorporated SR-IOV support to better serve Cloud customers.

SR-IOV is a technology that enables a Cloud server to partition itself into multiple vertical slices, each capable of hosting a VM with its own share of CPUs, RAM and SSD storage. SR-IOV associates a separate PCIe^® address for the SSD namespace associated with each VM.

Advantages of SR-IOV in Cloud Servers

• SR-IOV enables data centers to accommodate a higher number of applications within the same physical space
• It lowers the cost associated with hosting applications
• It allows the data centers to better manage the resources needed by the application
• It enhances the data center’s ability to adapt to changing requirements
• It facilitates increased automation, thereby improving the efficiency and effectiveness of the data center

How many customer applications can be hosted on a single Cloud server? There is no definitive answer to this question, as applications vary significantly in their needs for CPUs, RAM and SSD storage.

Over time, applications tend to expand and demand more storage. Concurrently, Cloud servers are evolving with more powerful and efficient CPUs clusters, increased RAM (using CXL) and advanced SSDs that offer greater capacity and performance to accommodate these growing needs.

Sustained Growth Comes With New Challenges

There are new requirements for a more efficient way to migrate applications to a new, appropriately sized footprint.  The objective is to transfer an application from one VM to another VM that better matches the resource needs. This may involve moving an application to a new server—without affecting the reliability and up-time of the application.

There is also an increased emphasis on security. The server, along with its hardware, firmware and software components, must support the latest evolving security standards. SR-IOV can use TEE to secure its private communication path.

Enhancements to SR-IOV were proposed by Intel^® in 2018 under the name Scalable I/O Virtualization (SIOV). This proposal includes ideas for creating more efficient data pathways on the host, separating queues for fast-path I/O and slow-path configuration and increasing the number of SR-IOV data pathways from 256 to 4096. It also suggests numerous additional options for an SR-IOV endpoint beyond just NVMe namespaces.

SR-IOV is extending its application beyond cloud data centers. It is now being utilized in non-cloud data centers and has already been implemented in sophisticated CAD system environments.

Who Will Influence the Expansion of SR-IOV?

The driving force behind progress is that NVMe SSD suppliers constantly strive and invest to meet the needs of their customers. However, Cloud and datacenter customers should work cohesively to discuss the use and needs for SR-IOV. It is important for customers to try to look ahead and to make their NVMe SSD suppliers aware of their needs for SR-IOV, number of VFs and their needs for TEE. 

Vendors can look for SR-IOV requirements to show up in customer requirement specifications that get shared with their suppliers. This allows the suppliers the lead time necessary to respond confidently and effectively to include the appropriate features needed in the marketplace for their upcoming products.

On a smaller scale, you can share this article with your colleagues to foster engagement. We also welcome your feedback and ideas by contacting the author. Be sure to check out our NVMe SSDs page.