v.21.9Improvement

Split Global Mutex for Individual Regexp Construction to Improve Thread Performance

Split global mutex into individual regexp construction. This helps avoid huge regexp construction blocking other related threads. #27211 (Amos Bird).
Split the global mutex used for regular expression construction into individual mutexes for each regexp, reducing contention and blocking.

Why it matters

This feature addresses the problem of thread blocking due to a single global mutex during regexp construction. By splitting the mutex, multiple regexp constructions can proceed concurrently without waiting, improving performance and reducing thread contention.

How to use it

The change is internal and transparent to users. No explicit action is required; users benefit automatically from improved concurrency when using regexp-related functions.