How KEDA HTTP Add-on for Autoscaling HTTP request on Kubernetes works

The KEDA HTTP Add-on enables autoscaling for HTTP-based workloads in Kubernetes. Unlike traditional event sources, HTTP traffic is unpredictable and synchronous, requiring a unique approach to autoscaling. The KEDA HTTP Add-on architecture comprises an Interceptor that holds incoming requests, an External Scaler that monitors pending requests, and an Operator that manages autoscaling configuration. HTTP requests are received by the Load Balancer and routed to the Interceptor, which queues requests if no backend pods are available. The External Scaler communicates with the Interceptor to determine scaling requirements based on request volume. KEDA evaluates scaling decisions and triggers scaling actions, such as creating new pods to handle increased traffic or scaling down to zero when traffic subsides. Key benefits of KEDA HTTP Add-on include scale-to-zero support, dynamic scaling based on HTTP requests, and efficient traffic handling. Challenges include a complex setup process, potential scalability limitations at extreme traffic volumes, and compatibility considerations when using other scaling mechanisms. KEDA HTTP Add-on provides a comprehensive solution for autoscaling HTTP-based applications in Kubernetes, reducing resource waste and ensuring responsive services without manual intervention.