KVM For Linux 5.10 Brings New "TDP" MMU To Help VMs With Hundreds Of vCPUs, TBs of RAM

Written by Michael Larabel in Virtualization on 24 October 2020 at 08:38 PM EDT. 3 Comments
The Kernel-based Virtual Machine (KVM) is seeing plenty of improvements with the Linux 5.10 kernel.

Among the KVM hypervisor work coming in at the tail end of the Linux 5.10 merge window includes:

- The new Two-Dimensional Paging "TDP" x86 MMU being contributed by Google. This KVM MMU implementation is running at Google already and this implementation can now handle the company live migrating 416 vCPUs with 12 TiB "m2-ultramem-416" virtual machines without issues compared to the existing MMU code. This code can now handle page faults in parallel for large VMs where as the existing KVM code would suffer "extreme contention" if having VMs with hundreds of virtual CPUs and terabytes of RAM.

- ARM has new page table code for the hypervisor and guest stage two.

- ARM now supports a new EL2-private host context.

- ARM has a complete rework of its Spectre mitigation handling.

- INVPCID support on AMD CPUs with the instruction now supported on Zen 3 CPUs.

- A cleanup to the nested AMD code.

- Various other low-level KVM improvements.

More details on the KVM changes for Linux 5.10 via this pull request.
Related News
About The Author
Michael Larabel

Michael Larabel is the principal author of Phoronix.com 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 OpenBenchmarking.org automated benchmarking software. He can be followed via Twitter, LinkedIn, or contacted via MichaelLarabel.com.

Popular News This Week