The Enhanced Monitoring feature uses InfluxDB and Grafana.
Both InfluxDB and Grafana servers need a balance between CPU and RAM in a 1:2 ratio. The needed resources depend on how many servers are sending metrics every second, how long are the ranges used for displaying the dashboards and how detailed are the charts in terms of granularity.
For example if you choose to display the metrics for a dashboard for the last month you can experience delayed responses or even failed responses if the resources are not enough.