nvidia-smi on a busy card can take past the 3 s deadline, which latched the card
as stalled until restart. A late read now carries the last readings and is used
when it lands; no second read starts while one is out; only one out for 15 s
(past both nvidia-smi timeouts) marks the card stalled, and its return clears it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>