Are the days of SR-IOV (Single Root I/O Virtualization) numbered? SR-IOV was originally designed for 20 or so VMs with most instances using 8 vCPUs or less. Now that we have 60-128 cores/120-256 hw threads and beyond with multiple sockets and CXL, things have changed.

Scalable IO offers better scalability, flexibility, over-provisioning, and a Scalable IO system can still support traditional SR-IOV in backwards compatibility mode.

It does this with hardware-assisted, efficient routing and has different modes for direct and intercepted path functionality. I won’t claim I fully grock all the details, but it does seem like a great way to start taking advantage of newer architecture enhancements we’re seeing in a wide variety of upcoming hardware platforms.

Give the spec a read to learn more.

Links:

• https://www.opencompute.org/documents/ocp-scalable-io-virtualization-technical-specification-revision-1-0-version-1-3-pdf
• https://www.intel.com/content/www/us/en/docs/programmable/813754/24-1-4-0-0/scalable-iov.html
• https://www.servethehome.com/microsoft-and-intel-scalable-io-virtualization-replacing-sr-iov-ocp/