By default, Kubernetes allows pods to consume system resources such as CPU and memory without many constraints. This can lead to several risks:
Resource Contention: Without proper limits, a pod can consume all available CPU or memory, starving the system or other pods of resources. This can lead to degraded performance or even system failures.
Cluster Instability: Unrestricted resource usage by one or more pods may cause essential system services to fail due to lack of resources, potentially causing the entire cluster to become unresponsive.
Denial of Service (DoS): In environments with multiple namespaces or users, a single namespace or user could exhaust all available resources, leading to a denial of service for other users or services.
To mitigate these risks, it is crucial to configure resource quotas, limit ranges, and reserve resources for system operations.
