Linux Patches Improve KVM Guest Performance For Hosts Under Memory Pressure

Written by Michael Larabel in Virtualization on 17 February 2023 at 07:27 AM EST. 4 Comments
Google engineer Yu Zhao known for his work on MGLRU has published a new patch series today that "significantly improves" the KVM guest performance when the host system is under heavy memory pressure.

The new patch series is "mm/kvm: lockless accessed bit harvest" that Yu Zhao sums up as:
"This patchset RCU-protects KVM page tables and compare-and-exchanges KVM PTEs with the accessed bit set by hardware. It significantly improves the performance of guests when the host is under heavy memory pressure.

ChromeOS has been using a similar approach since mid 2021 and it was proven successful on tens of millions devices."

These Linux KVM patches deal with optimizing the guest performance when the host memory is over-committed. More comprehensive benchmarks to showcase the performance improvements of these five patches are said to be coming soon.

This new patch series is coming too late to see it for v6.3 but hopefully everything pans out and we'll be able to see this Linux KVM optimization tuning for a kernel release later in 2023.
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