The include_empty folder tree (download/move modals) walked every model
root synchronously on the event loop via get_all_folders(). On network
(NAS) roots this froze the whole server for the duration of the walk —
blocking WebSocket progress, aria2 RPC and the download queue — and the
5s TTL re-triggered the walk on nearly every modal interaction.
The scanners already visit every directory during cache scans, so record
the full directory list (including empty folders) there instead:
- _gather_model_data/_reconcile_cache collect directories during the
existing walks; reconcile refreshes and persists the list even when no
model files changed.
- ModelCache gains an all_folders field (None = never recorded).
- PersistentModelCache stores the list in a new folders table, with a
cache_meta flag distinguishing 'recorded empty' from legacy snapshots.
- get_all_folders() is now a pure in-memory read. A legacy snapshot
triggers a one-shot backfill walk in a worker thread (never on the
event loop) that records and persists the list.
- Moves add the destination folder (and parents) incrementally instead
of invalidating a TTL cache.
Will Miao
6d3f82976f