v.22.11Improvement

system.asynchronous_metrics documentation added and cache disk metrics error fixed

The system.asynchronous_metrics gets embedded documentation. This documentation is also exported to Prometheus. Fixed an error with the metrics about cache disks - they were calculated only for one arbitrary cache disk instead all of them. This closes #7644. #43194 (Alexey Milovidov).
The system.asynchronous_metrics table now includes embedded documentation, which is also exported to Prometheus. Additionally, the calculation of cache disk metrics has been fixed to correctly aggregate data for all cache disks instead of just one arbitrary disk.

Why it matters

This feature improves the usability and accuracy of asynchronous metrics by providing detailed embedded documentation directly in the system.asynchronous_metrics table and ensures Prometheus exports benefit from this documentation. Fixing cache disk metrics aggregation resolves inaccuracies, enabling users to monitor cache disk usage comprehensively across all disks.

How to use it

Users can query the system.asynchronous_metrics table to view the updated metrics along with their embedded documentation. Prometheus scraping of ClickHouse metrics will automatically include this improved documentation. No additional configuration is required to benefit from the fixed cache disk metrics.