Toro is a x64 kernel that dedicates all system resources to the embedded user application. The result of the compilation of Toro is an image that contains both the kernel and the application. The kernel image can be booted by all majors hypervisors Hyper-V, KVM, VMWare ESXi, and emulators Qemu, VMWare WorkStation, VirtualBox. In these environments, the application runs directly inside the kernel without the need of a general purpose operating system. In this talk, I will present recent experimentation in which the scheduler of Toro is optimized to reduce the CPU usage of a VM. It has been identified three cases in which the scheduler can be optimized to reduce the impact of idle loops. To validate these techniques, I will present the impact of the improvements on a live running Toro VM on top of QEMU and Hyper-V. Open questions are welcome throughout the session to discuss the benefits and drawbacks of this approach but also take-away lessons.
Speakers: Matias Vara