(From the Netflix PDF) Each appliance stores a portion of the catalog, which in general is less than the complete content library for a given region. Popularit

(From the Netflix PDF) Each appliance stores a portion of the catalog, which in general is less than the complete content library for a given region. Popularity changes, new titles being added to the service, and re-encoded movies are all part of the up to 7.5TB of nightly updates each cache must download to remain current. We recommend setting up a download window during off-peak hours when there is sufficient free capacity.