v.23.3Improvement

ThreadPools Metrics Introspection by Azat Khuzhin

ThreadPools metrics introspection. #47880 (Azat Khuzhin).
Introduces introspection metrics for ThreadPools in ClickHouse to monitor thread pool usage and performance.

Why it matters

This feature enables users to observe and analyze the internal behavior and resource utilization of ClickHouse thread pools, helping to diagnose performance bottlenecks and optimize configurations.

How to use it

Users can access new ThreadPools metrics via the system tables or monitoring interfaces available in ClickHouse, allowing integration with external monitoring tools for real-time observation.