One-click way to force a library rescan on a remote computer?

[TheDreadPirate]

How well real time monitoring works over SMB depends on the device running SMB server. Each file being monitored over needs an individual inotify watcher process/thread and the host OS caps that number. 8196 is the default most of the time. That can be increased on plain Linux, but each inotify watcher uses a fixed amount of memory. If you have more files than the allowed number of inotify watchers, real time monitoring won't work for the remaining files.

Because your SMB server is a QNAP NAS, I am not sure whether their OS will allow you to modify how many inotify watchers are allowed.