Cloud Hypervisor 21.0 Offers More Efficient Local Live Migration: 3s Down To 50ms

Written by Michael Larabel in Virtualization on 23 January 2022 at 04:36 AM EST. Add A Comment
Cloud-Hypervisor 21.0 was released this past week as its first feature release since this open-source Intel project moved to the Linux Foundation with backing from Microsoft and Arm. Cloud-Hypervisor 21.0 brings new features and fixes to this Rust-written hypervisor.

The main feature introduced with Cloud-Hypervisor 21.0 is efficient local live migration for handling fast live upgrades of this VMM. This efficient local live migration is optimized to the extent that a live upgrade can now complete in as little as 50ms rather than 3s. This more efficient live upgrade is handled by passing of the file descriptors over the UNIX socket. The 50ms vs. 3s comparison was done on a booted 4GiB virtual machine.

Cloud-Hypervisor 21.0 also ships fixes to its OpenAPI YAML file to better match the implementation, supports live migration within firmware, "direct=on" can now be used with a guest that makes unaligned accesses, and various other fixes.

Intel, Google, Microsoft, China Telecom, and Arm were among the organizations that contributed to this Cloud-Hypervisor 21.0 release now under the stewardship of the Linux Foundation.

Downloads and more details on Cloud-Hypervisor 21.0 over on the project's GitHub.
Related News
About The Author
Michael Larabel

Michael Larabel is the principal author of and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 20,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and automated benchmarking software. He can be followed via Twitter, LinkedIn, or contacted via

Popular News This Week