A single pod whose vLLM failed to start (another vLLM still held 37 of its
47 GB) answered 503 to every page. _read_on_pods set the whole pool's pod
pipeline aside for 300 s on that one answer, so every page in that process was
read on the orchestrator. Live, that meant ~10 pages/s from 34 pods, with the
orchestrator's CPU doing the reading.

Now a refusal takes that pod out of rotation (lease.dead -> quarantine) and
the page tries another pod. The pool is set aside only when a page's attempts
were refused by at least two different pods, i.e. when it looks like the
image and not one card.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KnfkxBpcZ1v6ypRFFyhrVM