I use inotify-tools and unison to synchronize folders between machines.
Because I have a large folder to synchronize, I just simply write an inotifywait script to do the job automatically.
Is it sensible to let inotifywait to monitor the subdirectories of the large folder to gain a better performance?
You should get better performance if you ditch inotify-tools and just use unison's native support for watching your folders for changes. By using inotify-tools and then calling unison when a change occurs, unison has to "re-find" the change before it syncs. You could instead add the line repeat = watch to your unison profile and unison will run continually and sync whenever there is a change. It detects the change with its own file-watcher utility unison-fsmonitor that communicates directly with unison.
For more information, check out the latest changelog for unison 2.48.3 with major changes to unison-fsmonitor.
来源：https://stackoverflow.com/questions/16496624/gaining-better-performance-with-inotify-tools-and-unison