5 Replies Latest reply on Mar 30, 2017 8:49 AM by JCopenhaver

    Strange CPU use


      While rendering from After Effects CC2017 my CPU use is, for lack of a better term, spikey. It rapidly goes high, then low, then high....


      I am not sure what is wrong. It could be my system but I can't locate the issue. Does anyone have any suggestions? I've never seen After Effects do this before so I am obviously a bit concerned.


      My system is made up of the following:

      Dual Xeon E5-2650 V1 8-Core processors at 2GHz

      AMD FirePro W7000 GPU (Adobe tells me that my drivers aren't compatible, though)

      128 GB DDR3 RAM

      4 WD Blue 7200 RPM HDDs in RAID 0

      1 Samsung 850 SSD for OS

      1 Samsung 840 SSD for Project Files

      1 Hitachi 7200 RPM HDD for Cache Files


      AE_CC17 spikes use.PNG

        • 1. Re: Strange CPU use
          Mylenium Most Valuable Participant

          And what exactly? Without any info on the specifics of the project, comp settings, render settings etc. this is of no use to anyone. That aside, the performance graphs look perfectly reasonable for AE - render a frame/ comp/ effects buffer, wait for it to be stored to file, move on to the next frame. Perfectly natural that any of these steps will see a different CPU usage and idle cycles.



          • 2. Re: Strange CPU use
            JCopenhaver Level 1

            It's like this with every project. I have changed the Mercury Render from "Software Only" to "GPU accelerated" and that seems to smooth it out some, but it's just smaller spikes. This seems strange to me since Premiere and AE tell me they can't use the GPU (even though it is an approved card).


            It doesn't act like this on other computers, which leads me to think it's something with this particular system. I just can't seem to find the issue.

            • 3. Re: Strange CPU use
              Mylenium Most Valuable Participant

              I'm not sure what you expect. You have 32 cores in your system (16 physical ones, 16 HT ones) of which AE will only use 2 or 4 most of the time. The rest is just the lack of precision in how the graphs are sampled. Given your system, it's really perfectly normal. You simply expect AE to work in a way it doesn't. Your Xeon system is less than ideal because of AE's limited multithreading to begin with and of course that being the case, the per-core efficiency is lower, introducing more wait cycles for the cores that have nothing to do while the others are busy. The same could be said for al lthat GPU stuff - eliminating a few idle cycles will of course result in a smoother graph, but that doesn't change the fact that AE sucks at using your system's resources. That's just how it is. I'm afraid you have bought the wrong kind of system and now are looking for magic buttons.



              1 person found this helpful
              • 4. Re: Strange CPU use
                Dave LaRonde Level 6

                Relax.  Don't sweat the details on this.  Your machine and AE are working just fine. 

                I think you have far more important things to worry about, such as learning how to use AE.

                • 5. Re: Strange CPU use
                  JCopenhaver Level 1

                  Thanks for the info, Mylenium. I'm still learning the ins and outs of AE so I was concerned when I saw this happening on just this system. I wasn't aware there was a limit to how much power AE could utilize. If you have some resources for me to read up on, that would be appreciated. If not, I hope you have a great day.