emqx4.3/changes/ce/feat-13873.en.md

Improve /api/v5/monitor endpoint performance.

Prior to this enhancement, the dashboard monitor page often timeout when there are many nodes in the cluster. Below are detailed changes:

• Make concurrent RPC calls towards nodes in the cluster to retrieve metrics.
• Data points are downsampled to reduce dencity. Dencity is adjusted according to the requested time span in the query:
  • 10s when query the last 1h
  • 1m when query the last 1d
  • 5m when query the last 3d
  • 10m when query the last 7d
• Insert dummy data points for gaps in the timeline (if EMQX has stopped for a while), so the gap will be visible in the dashboard.