Another problem with the configuration reloading is that all the backend/service metrics counters that HAProxy exposes on its metrics endpoint get reset on ever

Another problem with the configuration reloading is that all the backend/service metrics counters that HAProxy exposes on its metrics endpoint get reset on every reload. That makes for really noisy metrics gathering in situations where you have rapid successive changes to the config, such as gradually scaling up hundreds of instances of a new version of a microservice and then scaling down the old version. When you then scrape the metrics via Prometheus using an bridge like HAProxy Exporter (https://github.com/prometheus/haproxy_exporter https://github.com/prometheus/haproxy_exporter), you lose a lot of counter increments due to the frequent resets, so you get lower and noisy rates for that time period.