use RDM cause windowServer get high

[Sev73n]

usual use The normal resolution is 500mb

[Sev73n]

The window switch becomes very cotton

[ijoseph]

+1 : I had to stop using this to increase my resolution on my 2012 MBP because WindowServer was taking an absurd amount of CPU and Memory, rendering my system nearly-unusable.

However, I think my later MBP (2018) can handle it without too much complaint.

This perhaps isn't quite a bug (I doubt it can be fixed; it's just due to inherent resource constraints) and more of a PSA.

Example

I believe 80% is across all cores (rather than per-core) here. Interestingly, the dips are where I stopped using my laptop; it appears that using it triggers the WindowServer to use high CPU, which is consistent with the hypothesis that it's WindowServer itself struggling to render, rather than some upstream, non-WindowServer process actually causing the issue.