One of the main problems on a shared hosting system for file backup operations is to figure out which files have changed. Using INOTIFY on a 1T drive with a large number of small files and directories guarantees slow startup times, and a lot of context switching between kernel and userspace - generating additional load. On the other hand scanning disk for newly modified files is very IO intensive, and can kill the performance of the fastest disks.
CloudLinux File Change API is a kernel level technology with the user space interface that buffers lists of modified files in the kernel and then off-loads that list to user space daemon.
After that - any software (with enough permissions) can get a list of files that has been modified for the last 24 hours.
The software is very simple to use and produces the list of modified files. As such we expect file backup software, including integrated cPanel backup system to integrate with this API soon.