The remaining /model picker stall after the Copilot backoff fix: whenever
the 1h provider-models disk cache TTL (or the remote model-catalog manifest
TTL) lapsed mid-session, the next picker open blocked on 8-9 serial
/v1/models round-trips (~2-3s measured) plus the catalog manifest fetch
before rendering anything.
Model catalogs change on release timescales, not hourly — so both caches
now use stale-while-revalidate:
- cached_provider_model_ids(): an expired entry whose credential
fingerprint still matches is served immediately; a deduped daemon thread
re-fetches the live catalog and rewrites the disk cache for the next
open. Entries older than 7 days still block on a live fetch, credential
rotation still busts the entry, and force_refresh still bypasses SWR.
- model_catalog.get_catalog(): an expired disk manifest is served
immediately with an off-thread refresh; only a truly cold cache (no disk
copy) blocks on the network.
Measured picker payload build with deliberately-expired caches:
2.9s -> 0.93s (first open in process) / 0.06s (subsequent opens).
Combined with the Copilot fix (#76386): 7.3s -> ~0.06s for the common case.
Teknium