lgtm

@greptile review

Greptile Summary

This PR optimizes the handler dispatch mechanism by implementing a copy-on-write pattern with proper cross-thread visibility guarantees. The changes eliminate locking on the hot path (Invoke) while maintaining thread safety through Volatile.Read/Write.

Key improvements:

• Replaced lock-based copying in Invoke with lock-free snapshot reads using Volatile.Read
• Added _handlerSnapshot array field initialized to Array.Empty<HandlerItem>()
• Updated snapshot with Volatile.Write after modifications in Register and UnRegister
• Added conditional snapshot update in UnRegister to avoid unnecessary allocations when no handlers are removed
• Added early return optimization when handler list is empty

Thread safety analysis:

• Modifications (Register/UnRegister) remain protected by HandlerLock
• Volatile.Write ensures snapshot updates are visible across threads with proper memory barriers
• Volatile.Read in Invoke guarantees consistent snapshot visibility without tearing
• Snapshot arrays are immutable after creation, preventing concurrent modification issues

The implementation correctly balances performance (lock-free reads) with safety (volatile semantics for visibility). No issues found.

Confidence Score: 5/5

• This PR is safe to merge with no risk
• The implementation correctly uses the copy-on-write pattern with proper volatile semantics for cross-thread visibility. Lock protection for mutations prevents race conditions, while lock-free reads optimize the hot path. The code is focused, well-structured, and introduces a clear performance improvement without compromising thread safety.
• No files require special attention

Important Files Changed

_{Last reviewed commit: 1736b23}