Load Balancer Tuning: Comparative Analysis of HAProxy Load Balancing Methods

Load balancing is prevalent in practical application (e.g., web) deployments seen today. One such load balancer, HAProxy, remains relevant as an open-source, easy-to-use system. In the context of web systems, the load balancer tier possesses significant influence over system performance and the incurred cost, which is decisive for cloud-based deployments. Therefore, it is imperative to properly tune the load balancer configuration and get the most performance out of the existing resources. In this technical report, we first introduce the HAProxy architecture and its load balancing methods. Then, we discuss fine-tuning parameters within this load balancer and examine their performances in face of various workload intensities. Our evaluation encompasses various types of web requests and homogeneous and heterogeneous back-ends. Lastly, based on the findings of this study, we present a set of best practices to optimally configure HAProxy.