Experiment 032: Completer.sync in Pool Dispatch

Date: 2026-04-09

Status: Accepted

Change

Replaced Completer<T>() with Completer<T>.sync() in reader_pool.dart for

the per-request completer, the worker available notification, and the spawn

handshake. Sync completers fire synchronously instead of scheduling a microtask.

Results

No isolated signal in aggregate benchmarks (expected — saves ~1 microtask per

query, which is ~10-50µs). Part of the cumulative +17% point query improvement.

Decision

Accepted — one-word change, zero risk. Eliminates unnecessary microtask

scheduling on every query response.