The rate at which data is refreshed in the UI depends on the feature and the collection intervals. Generally, the UI fetches a new set of data from the database every 2 minutes and caches it to reduce network traffic. The performance counter and availability group monitoring pages refresh automatically every 30 seconds; other pages refresh their data (from cache or database) when you click on something.
The data collection intervals are:
- Server-level counters: 1 minute
- Instance-level counters: 1 minute
- Database-level counters: 1 to 60 minutes, depending on database count
- Availability groups: 2 minutes
- Standard alerts: 1 minute
- Pattern-oriented alerts. 5 minutes
- Predictive alerts: 5 minutes
- Anomaly detection: 24 hours
- Plan cache: 10 minutes
- Wait statistics: 1 minute
- SLAs: daily
- Blocks: 30 minutes
- Trace: milliseconds