I have few incremental backup jobs to google drive that are running every day and every time the jobs are running my pc is running slow. Why is that?
You’d probably have to take a look yourself, for example in Task Manager → Performance, especially your CPU and Disk utilization. If you have a mechanical hard drive (not an SSD), it’s very easy to keep it busy by checking lots of disk files – which pretty much by definition is what a backup has to do to find changed files, then back up. There are ways to lighten the impact, for those who want to slow Duplicati to favor other work.
HDD-access speed during backup speaks mostly to reducing the impact ot disk accesses, but I think it gets into CPU a bit. It also doesn’t get into the –usn-policy option which reduces disk use of finding changed files. FailedToUseChangeJournal covers Administrator permissions it may need for a non-service Duplicati install.
With PC resources being shared, you might also notice different sorts of “running slow” depending on what you’re running. Disk-very-busy might not bother a CPU-intensive program much, but would slow a disk-user.