Building Burstables: CPU slicing with cgroups

Building Burstables: cpu slicing with cgroups Maciek Sarnowicz Contributor Ubicloud is an open source alternative to AWS. You can self-host our software or use our managed service to reduce your cloud costs by 3x. ‍Some of our customers told us that the price of dedicated VMs was too steep and asked for a lower entry point. We looked into it and came up with burstable VMs. These VMs run on a fraction of a shared CPU and burst to a higher level of CPU usage to support occasional spikes in usage. To implement burstable VMs, we leveraged Linux Control Groups v2 (cgroups v2), a Linux kernel feature that helps manage resource usage. We thought our open-source implementation of burstable VMs might be interesting enough to write about. We also learned a lot about Linux cgroups in the process! The building blocks Linux cgroups are organized hierarchically. Each group acts as a “container” that can host child groups, processes, and threads. These groups control specific system usage, ... Read full article.