Overview of the Global Profiling Engine

The Global Profiling Engine collects stick table data from all HAProxy Enterprise nodes in a cluster. It can perform calculations on both current and historical data before pushing the data back to the load balancers, giving them all a comprehensive and up-to-date view of client behavior across the cluster.

For example, in an active-active load balancer configuration where traffic is relayed to two or more load balancers in a round-robin rotation, the GPE ensures that each load balancer receives the sum of requests that a client has made, even when some of those requests were routed to the other load balancer.

It calculates statistics for current, real-time traffic, which you can use to take action based on an immediate threat, such as a web scraper. It also calculates historical statistics, which you can use to make decisions based on traffic trends from the past. For example, you can factor in the request rate at the 90th percentile from yesterday.

The Global Profiling Engine should be installed on a separate server from your HAProxy Enterprise nodes, from where it can collect and aggregate data from stick tables from across your load balancer cluster.

When would you use the profiling engine? The table below outlines various, common ways to set up your load-balancing cluster and explains which benefit from using the Global Profiling Engine:

Standalone load balancer

If you operate a single HAProxy Enterprise node, collecting data with stick tables can help improve security and observability by monitoring client activity in real time. However, you do not need to use the Global Profiling Engine because there aren’t multiple load balancers collecting data that needs to be aggregated, unless you want to use its historical aggregations feature.

Active-standby cluster

In an active-standby cluster, you operate two HAProxy Enterprise nodes as peers, with one peer actively receiving traffic while the other is on standby. If you define a peers section in your configuration, then the stick tables of the active node are propagated to the passive node, where they overwrite existing values. Overwriting would be bad if both peers were receiving traffic and collecting data, but in an active-passive scenario, it’s perfectly fine. The metrics stay accurate on all nodes. In this case, you do not need the Global Profiling Engine, which aggregates data from multiple, active peers, unless you want to use its historical aggregations feature.

Active-active cluster with Global Profiling Engine

In an active-active cluster, you operate two HAProxy Enterprise nodes as peers, with both receiving traffic at the same time. To ensure that stick table counters are accurate cluster-wide, you need the Global Profiling Engine, which runs on a separate server, collecting stick table data from both peers and aggregating it. Once aggregated, the data is sent back to the peers so that they can make decisions based on it.