/api/status is the desktop's boot liveness probe (polled ~1/s) but since
#60537 every call ran a full topology scan — per-profile yaml.safe_load
(pure-Python loader), psutil process probes, realpath walks — in the
default executor. On multi-profile installs concurrent polls pile up and
hold the GIL 14-16s, starving the event loop: the WS sidecar cannot
flush gateway.ready, the desktop times out into the next stall, and boot
escalates to the 'Hermes couldn't start' overlay (#60800).
Memoize the scan behind a 10s TTL with a collapse lock so concurrent
polls share one scan. Topology only changes on gateway start/stop, so a
<=10s stale badge is an acceptable trade for not starving the loop. The
cache also keys on the collector's identity: tests monkeypatch
_collect_profile_gateway_topology per case, and the identity check keeps
them hermetic (a swapped collector is a miss) without a reset hook.
py-spy captures during a failing boot land in _profile_platform_ports ->
yaml.safe_load on executor threads (7 profiles, Windows). After: one
cold-start scan, zero recurring stalls, desktop boots.
lost9999