Method _monitor_loop

Lib/profiling/sampling/_child_monitor.py:170–202

(self)

                pass

    def _monitor_loop(self):
        # Note: There is an inherent TOCTOU race between discovering a child
        # process and checking if it's Python. This is expected for process monitoring.
        while not self._stop_event.is_set():
            try:
                self._poll_count += 1

                # Periodically clean up completed profilers to avoid memory buildup
                if self._poll_count % _CLEANUP_INTERVAL_CYCLES == 0:
                    self._cleanup_completed_profilers()

                children = set(get_child_pids(self.parent_pid, recursive=True))

                with self._lock:
                    new_children = children - self._known_children
                    self._known_children.update(new_children)

                for child_pid in new_children:
                    # Only spawn profiler if this is actually a Python process
                    if is_python_process(child_pid):
                        self._spawn_profiler_for_child(child_pid)

            except ProcessLookupError:
                # Parent process exited, stop monitoring
                break
            except Exception as e:
                # Log error but continue monitoring
                print(
                    f"Warning: Error in child monitor loop: {e}",
                    file=sys.stderr,
                )

            self._stop_event.wait(timeout=_CHILD_POLL_INTERVAL_SEC)

    def _cleanup_completed_profilers(self):
        with self._lock: