I have used micrometer.io for most of my career to collect metrics. One of the coolest micrometer features is binding to collect information about the host system and jvm: https://micrometer.io/docs/ref/jvm on the basis of which it was possible to run the Grafana dashboard without much effort: https://grafana.com/grafana/dashboards/4701
Currently, I am starting to learn about OpenTelemetry, but I cannot find a description of the above functionalities. I do not want to use instrumentation, I want to depend on a manual definition of what is to be measured. Can you show me a way to do this? How to easily manually provide system/JVM metrics?
See Is there an equivalent of Prometheus simpleclient_hotspot with Opentelemetry?.
You can use opentelemetry-java-instrumentation and manually register JVM metrics observers.