change on system requirements (#3677)

Author: woutslakhorst

docs/pages/deployment/recommended-deployment.rst

@@ -155,4 +155,4 @@ Below is a list of items that should be addressed when running a node in product
    - Only allow public access to ``/public``, ``/n2n`` and gRPC endpoints (but the latter 2 still require a client certificate).
    - Make sure ``/internal`` is properly protected
 - Availability
-   - Consider (D)DoS detection and protection for ``/public``, ``/n2n`` and gRPC endpoints
+   - Consider (D)DoS detection and protection for ``/public``, ``/n2n`` and gRPC endpoints

docs/pages/deployment/resource-requirements.rst

@@ -3,14 +3,22 @@
 Resource Requirements
 #####################
 
-The Nuts node is built to be lightweight in terms of CPU and memory usage. Proof: it even runs on a Raspberry PI (Zero).
+The Nuts node is built to be lightweight in terms of CPU and memory usage.
 
-For a production environment you should be able to run it on a small cloud VM, which typically start at;
+The minimum system for **development** and **test** are:
 
 - 1 CPU
 - 512 MB RAM
 - 25 GB storage
 
+Recommended system requirements for production depends on the expected load and use cases.
+It's recommended to keep track of the system's performance and adjust the resources accordingly.
+CPU and memory usage, and the API response times are good indicators of the system's performance.
+Make sure the CPUs are of a decent speed, as some operations are CPU-bound.
+The exposed metrics for ``process_cpu_seconds_total``, ``go_gc_duration_seconds_sum`` and ``go_memstats_alloc_bytes`` are a good starting point for monitoring CPU and memory usage.
+
+If you make heavy use of NutsAuthorizationCredentials, a minimum of 4 CPUs is recommended.
+
 Required storage depends on network state which grows over time, so make sure to monitor it.
 
 If you use Redis for network state storage the storage requirements will be lower,