Replace blind round-robin placement with load-aware strategy that reads
per-worker stats (actor count + mailbox depth) and biases toward lighter
workers. Falls back to round-robin when stats are equal (initial burst).
Deep research on work stealing across Tokio (steal-half, LIFO slot),
Go (M:N scheduler), BEAM (proactive migration), and ForkJoinPool.
Full actor migration is feasible but deferred due to message-loss window.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Replace thread::sleep with thread::park_timeout in worker backoff loop.
Workers register their thread handle via OnceLock<Thread> on startup.
When send_to or spawn routes work to a worker, Thread::unpark() wakes
it instantly instead of waiting for the sleep timer to expire.
Inspired by tokio's parker state machine and Linux NO_HZ adaptive ticks.
Implementation:
- Runtime stores Vec<OnceLock<Thread>> for worker thread handles
- Workers call OnceLock::set(thread::current()) on startup
- Runtime::send_any, spawn_any, and WorkerContext cross-worker sends
call notify_worker() → Thread::unpark() on the target worker
- TickContext carries worker_threads reference for cross-worker notification
- Zero new dependencies (std::sync::OnceLock + std:🧵:park_timeout)
Benefits:
- Parked workers wake instantly when work arrives (vs up to 1ms sleep delay)
- No overhead on hot path — unpark() is no-op if thread isn't parked
- Single-threaded tick() mode unaffected (OnceLock never set)
All 58 tests pass (52 runtime_api + 5 transport + 1 doctest).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Runtime dashboard now features a TUI option and an interface for LLM tool use. Removed some bloat from stats collecting and replaced with a hook function to dump runtime stats into.
