Linux KVM Continues Offering Much Better Out-Of-The-Box Performance Than VirtualBox

With the release earlier this month of Oracle VirtualBox 6.0, besides running some benchmarks of its VMSVGA 3D graphics support, I also ran some basic benchmarks to see how a similarly configured VM under both VirtualBox 6.0 with Linux KVM setup via virt-manager would compare for performance as we hit the end of 2018. This quick round of Linux virtualization tests was done on the AMD Ryzen Threadripper 2990WX system.

With the free VirtualBox 6.0 topping out at 16 vCPUs, that was what our tests were done with. The bare metal system was a Threadripper 2990WX having 32 cores / 64 threads while each VM had access to 16 cores (our bare metal tests also were configured so the system had just 16 cores online) and each VM had 16GB of RAM (of 32GB on the system) and the standard fixed storage size disk setup for each VM. On VirtualBox 6.0, KVM, and the host, Ubuntu 18.10 was running with the Linux 4.18 kernel. The settings and other packages were kept at their defaults.

The results didn't come out as a surprise and were similar to our past rounds of virtualization benchmarks involved VirtualBox:

While obviously the bare metal performance was the fastest, VirtualBox 6.0 was much slower than under KVM.

Here's a look at some of the individual results.