This is perfectly normal. Many of AE's effects are single-threaded and contrary to your assumption will not simply make your CPU glow to make up for it. Especially with temporal effects such as Remove Grain is, looking up multiple frames and processing them will also introduce additional IO overhead and whatnot that outweighs the actual processing time per frame. It could take hours to explain how AE handles this and which combinations cause these behaviors, but suffice it to say that for the time being you will have to live with it...
I was quite sure this was the case, but hoping for a different answer. After all the need for Reduced Grain is the result of improper camera/light settings. Far more benefit is gained by improving Camera/lighting setting then you could every get from Reduced Noise. But you know how it is, sometime you get caught without and had a good shot and.......
Thanks for keeping it accurate and to the point, that is exactly what I was looking for, and the answer was expected.
I don't know if you are the one to ask, but here it goes anyways. For programs and/or effects that are currently single-threaded, is it a big deal to make them multi-threaded?
Again, thanks for you help.
For programs and/or effects that are currently single-threaded, is it a big deal to make them multi-threaded?
Yes. And for a program as complex as AE, I would call it a huge deal.
Notice AE's kludge attempt to avoid doing it with the introduction of multiprocessing back in the day. (What was it, AE version 9 [CS4] that first introduced it?)
For the past year, the majority of the After Effects team have been working to rewrite the core of AE to be able to use multiple cores more efficiently. AE CC 2015 demonstrates the first step in this process; the interface (and your interactivity with it) is now on a separate thread from rendering. This allows us to have much snappier interface interactions and let the preview play while we make changes. In a future version, they plan to introduce much better/faster rendering. But don't take my word for it, they say as much in their discussion of the removal of multiprocessing here: features not available in After Effects CC 2015 (13.5) | After Effects region of interest
So, yes; it's a big deal, but to answer your next question, it is something the AE team is working on.
Thank you Szalam for your reply. After reading what I wrote,"For programs and/or effects that are currently single-threaded, is it a big deal to make them multi-threaded?" I could see how confusing my question was. Example: Why change it, what is the big deal to leave it as is OR is it technically difficult to change from single to multi thread. Which I meant the technically difficult. Please note, I am not writing this reply to you because it is obvious you knew just what I was asking, but for anyone else that may be unsure and I wanted to clarify.
I am not a programmer and don't want to pretend I know anything about programming. I can see the host of problems associated with the changes Adobe is going through. Can it be faster, better, more organized is a topic for another discussion. Of course the things that matter to me, I want changed now! But that ain't gonna happen, and everyone has their viewpoints. Me, I am happy to be witness to this transformation.
Having two very well spoken replies makes me very pleased to be part of the Adobe Family.