  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.
