I have a big directory that takes about 600GB with tens of thousands files. I need to synchronize it with my Qnap NAS. I tries BitTorrent Sync, but speed is very slow and it will take about a month for such transfer. Speed is about 10KB per second. If I copy it over AFP from my Mac the speed is about 50MB per second. Can I copy it over AFP and say for BitTorrent that these files are synced and same? If no, is there any other faster ways of syncing?
Getting the initial copy is the hard part, perhaps an external drive and sneakernet is best. Then you should consider rsync for keeping it up-to-date. Rsync may even be a good option for the initial sync too.