Reserved space contains resources set aside on a node, such as system daemons that back Kubernetes and the operating system itself. If these resources are not allocated sufficient reserved space, pods and system daemons will compete. This competition leads to starvation on the node.
Azure Kubernetes Service (AKS) addresses this issue by enforcing a rate at which it reserves space, as detailed by the Kube-reserved flag. This flag shows the resource reservation for Kubernetes system daemons including kubelet, container runtime, and more.
Beginning with AKS support of Kubernetes 1.29 in preview, optimized reservation logic reduces Kube-reserved memory by up to 20% depending on the node configuration and will apply to everyone.
