resolve_blob_hash() used to invalidate the cache entry immediately
after the first read, forcing every subsequent request for the same
file into a PG round-trip (~2-4 ms each). This is especially
costly for video Range Requests (50+ seeks = 49 unnecessary queries).
Fix:
- Remove self.hash_cache.invalidate(file_id) from resolve_blob_hash
- Add self.hash_cache.insert() on the slow path so even requests
that skip get_file() populate the cache for future reads
- This is safe: blob_hash is content-addressed (SHA-256), immutable
- moka TTI (30 s) + max_capacity (10 000) prevent unbounded growth
- Update 3 unit tests to verify persistent-cache semantics
Dionisio
71727faab4