Since a few weeks I suffer from the issue where I have to wait up to 6 sec after selecting an object in the viewport. The time depends on the amount of hidden layers (and hence the amount of objects visible). But the amount of objects visible from the moment this starts to happen are nowhere near stretching my system.
This question has been asked before, and I've been crawling through a number of bug-reports talking about this issue (or not) and they all seem to suggest that this should be fixed in later version. I'm working with Blender 2.79b and these bug-reports all seem to have this issue resolved for earlier version. So these fixes don't seem to apply for the current version anymore (or the features causing this are renamed, so I'm not recognizing them in the settings).
Also, the issue I'm having is often related to newe NVIDIA gpu's. I was using CUDA before (same computer, other arch-based installation) which seemed to perform way worse than my cpu when rendering, so I didn't jump through the hoops again to get it working. If I understand correctly CUDA has only an effect while rendering, it shouldn't affect performance while working in object mode, but maybe something I did driver-wise might have had an effect.
I've been struggling with this issue for a couple of weeks now, I hope someone can "render some lightrays onto my scene" ;-)
My laptop is a ASUS 4-core, some 2.5 Ghz, 16 Gb RAM with a Intel/Nvidia (bumblebee) GPU