Emit a grep-friendly '[MEMORY] rss=...MB ...' line in agent.log /
gateway.log every N minutes (default 5) so slow leaks in the long-lived
gateway process show up as a time series. Based on
https://github.com/cline/cline/pull/10343
(src/standalone/memory-monitor.ts).
- gateway/memory_monitor.py: new module. Daemon thread, baseline on
start, final snapshot on stop. Uses resource.getrusage() (stdlib)
first, falls back to psutil, disables itself with one WARNING if
neither is available.
- gateway/run.py: start monitor right after setup_logging() in
start_gateway(); stop it in the shutdown block next to MCP teardown.
- hermes_cli/config.py: logging.memory_monitor { enabled, interval_seconds }
defaults under the existing logging section.
- tests/gateway/test_memory_monitor.py: 10 unit tests covering format,
baseline/shutdown snapshots, double-start noop, periodic timer,
daemon thread invariant, and unavailable-RSS warn-and-skip path.
Adapted from TypeScript/Node to Python (threading.Event-based daemon
thread instead of setInterval/unref), added Python-specific gc + thread
counts to the log line (handier than ext/arrayBuffers for diagnosing
Python gateway leaks), and gated behind a config.yaml toggle so users
can silence the periodic line if they want.
No heap-snapshot-on-OOM equivalent — CPython doesn't have V8's
--heapsnapshot-near-heap-limit; tracemalloc would be the Python
equivalent but adds non-trivial overhead, so leaving that out.
