Windowserver spikes to 100% cpu opening one specific folder

Question

one issue keeps haunting my imac 27" (late 2013) running on maverick 10.9.4
everything runs pretty fine until i open one folder containing further folders with jpgs. the primary folder is 1.98 gb, but i have other folders on the external wd my book drive that are 78 gb heavy and don't have that issue of windowserver spiking up to 100 % cpu. the problem is limited to that one folder.
i have know idea, what makes that folder special. i didn't have these problems on my old imac, where i can open the folder, delete jpg etc. without any problem.
any suggestions?

Answer 1

It's probably a combination of Flash and video decoding. Flash is not coded very efficiently on the Mac and uses more CPU than it should. On an older machine, this can tax the CPU to its limit. You can watch CPU usage spike even on Flash sites that don't use video - try it sometime.
Second, the way that current video codecs get so much quality out of so little bandwidth is by applying encoding so intensive that you need a very powerful CPU to decode it. Codecs that assume they will be running on the 2GHz dual-core CPUs of the last few years will overtax the slower single-core G4 processors of half a decade ago.
I can watch Hulu and other videos on my PowerBook G4 at standard resolution (Hulu at a low frame rate, though), but the G4 cannot handle high quality resolution playback at all.
In your case, it's important to kill off any CPU-intensive processes that don't need to be running in the background when you're trying to watch something.