Beginner here. I started a few days ago and began using blender 2.8 yesterday. I'm not sure if it's normal but I notice my renders slow down in 2.8 when they're almost done. It didn't happen in 2.79. It's so much that the last 1 minute of time remaining takes 10 minutes. The image is also almost completely rendered, with almost no tiles showing any noise.
I have GPU and CPU rendering set up, my GPU is a gtx1080 and CPU is in i5-4670k at 4.5ghz. Not sure if that's relevant but thought I would add it.