This set of experiments tries to give an answer when a Open Data publisher can use HTTP polling and otherwise use publish/subscribe for real-time data.
This benchmark uses a Kubernetes cluster to scale up to a dozen of clients. One server is configured to deploy pull- and push-based interfaces. A gateway can be configured to add network impairment.
Research question: What is the cut-off point between HTTP polling and publish/subscribe (pubsub) interfaces for real-time Open Data?
Note: Server-Sent-Events (SSE) is tested for pubsub systems to use the same protocol (HTTP) as polling.
First, we want to test how many clients can be served with our server. This server has 3.7 GB of memory and uses a Dual-Core AMD Opteron(tm) Processor 2212 with 2010.276 MHz.
Hypothesis: Pubsub interfaces induce a linear amount of resources according to the amount of users.
Hypothesis: Pubsub interfaces have a constant total user latency according to the time between observations.