In the previous article we created a simple indexing code that hammers ElasticSearch with thousands of concurrent requests. The only way to monitor the performance of our system was an old-school logging statement: .window(Duration.ofSeconds(1)) .flatMap(Flux::count) .subscribe(winSize -> log.debug("Got {} responses in last second", winSize)); It’s fine, but on a production system, we’d rather have some centralized Monitoring ...