Performance Design

This document records the performance design direction; no systematic benchmarking has been done yet, and concrete numbers are to be filled in.

Core Principles

• Small core first; reduce startup path dependencies.
• Lua business logic does not touch CAF directly.
• Prefer send for business messages; avoid unnecessary synchronous waits.
• Every call must have an explicit timeout.
• The network layer only handles connections and byte streams; it does not carry business policy.
• Data access stays raw; avoid the extra complexity an ORM would introduce.

Paths To Evaluate

• Cost of converting between Lua tables and C++ payloads.
• Blocking semantics of shield.call inside Lua coroutines.
• Upper bound on the number of scheduled timers.
• Cost of TCP / UDP / WebSocket session management.
• Number of copies in transport framing and encryption paths.
• Whether raw DB / Redis calls block runtime threads.

Non-Core Performance Items

The following are not part of the current core performance goals:

• Prometheus metrics overhead.
• HTTP management endpoint latency.
• Middleware chain overhead.
• Service discovery backend latency.
• Plugin loading cost.

If these capabilities are added later as extensions, they should get their own performance budget.