Computing resource management is very important in any infrastructure. We should know our application well and preserve enough CPU and memory capacity to avoid running out of resources. In this section, we'll introduce how to manage node capacity in Kubernetes nodes. Furthermore, we'll also describe how to manage pod computing resources.

Kubernetes has the concept of resource Quality of Service (QoS). It allows an administrator to prioritize pods to allocate resources. Based on the pod's setting, Kubernetes classifies each pod as one of the following: 

• Guaranteed pod
• Burstable pod
• BestEffort pod

The priority is Guaranteed > Burstable > BestEffort. For example, if a BestEffort pod and a Guaranteed pod exist in the same Kubernetes node, and that node encounters CPU problems or runs out of memory, the Kubernetes master terminates the BestEffort pod first. Let's take a look at how it works.