You deployed an application into a large Standard Google Kubernetes Engine (GKE) cluster. The application is stateless and multiple pods run at the same time. Your application receives inconsistent…

A cron job scales on a fixed schedule, which is inefficient and ineffective for applications with inconsistent and unpredictable traffic patterns.

A Horizontal Pod Autoscaler automatically scales the number of pod replicas for a deployment up or down based on observed CPU utilization or other metrics, directly addressing inconsistent traffic to maintain consistent user experience and optimize resource usage.

A Vertical Pod Autoscaler optimizes resource requests and limits for *individual* pods, but it does not scale the *number* of pods to handle fluctuating traffic loads.

Cluster autoscaling manages the number of nodes in the cluster, but it depends on the number of requested pods; it doesn't directly scale the application's pods in response to traffic, making HPA necessary first to scale pods.