Instant change detection
From PowerFolder Wiki
Introduction
This option greatly helps to reduce the CPU and harddisk activity by listening for changes of the file system instead of performing periodic scans. Also files will get instantly synced with after being changed, created or deleted. This makes the synchronization faster and more direct.
It is enabled by default and will be applied on every folder. Change this under Folder/Settings/transfer mode. It also increases the time between file system scans for default transfer modes (e.g. auto-sync, backup source or share/send).