5 Replies Latest reply: Dec 17, 2010 2:54 PM by Dave LaRonde RSS

    AE CS5 not using all memory and cpu

    eVatrik Community Member

      I am using After Effects CS5, wondering why the rendering is not using my CPU and memory full. It`s using only 15 % of memory and sometimes up to 50 % of CPU. What can I do to make it use better my hardware.

      The current rendering is chroma key using Keylight.

       

      I understand it can`t use all the hardware, but why only 15 %, because everybody is talking that you need a lot of RAM for AE.

       

      CPU: Intel Core i7 920 - overclocked to 3.4 GHz

      MEMORY: 6 GB DDR3

      GRAPHIC: nVidia GTX 285

      aerender.jpg

        • 1. Re: AE CS5 not using all memory and cpu
          Todd_Kopriva Adobe Employee

          Not all rendering operations will max out all RAM and all CPUs (processor cores). Some rendering operations are I/O intensive; some are memory-intensive; some are CPU-intensive. If, for example, I/O is the bottleneck, then you won't see either CPU or RAM usage maxed.

           

          Also, the goal isn't to see that 100% of the CPU and 100% of of RAM is being used. The goal is faster rendering (and other operations). Sometimes greatest performance is achieved when there's "headroom" left over for other activity. See this page.

           

          Are you using Render Multiple Frames Simultaneously multiprocessing? That is one feature that really benefits from having a lot of RAM. The 6GB of RAM that you have in your system is not enough to make effective use of that feature. See this page.

           

          Here's a page that collects information about how to optimize for performance.

          • 2. Re: AE CS5 not using all memory and cpu
            eVatrik Community Member

            Thanks for reply

             

            Can I get a little bit faster rendering using After Effects Render Engine alone. I know it`s the same as in after effects, but maybe if it`s running alone without other after effects panels it`s better.

             

            And I also tried to render using openGL with gtx 285 graphic card, but the rendered video is not as good quality as when I render with CPU.

            Why is like that?

            • 3. Re: AE CS5 not using all memory and cpu
              Todd_Kopriva Adobe Employee

              >And I also tried to render using openGL with gtx 285 graphic card, but the rendered video is not as good quality as when I render with CPU.

              Why is like that?

               

               

              In After Effects, the OpenGL renderer is just a preview renderer; it's not intended for high-quality final renders. Writing rendering code for a GPU is different than writing rendering code for a CPU, and we don't waste our time rewriting every part of the rendering pipeline on the GPU to match that on the CPU.

               

              To reiterate: OpenGL rendering is just intended for fast previews when doing things like placing 3D layers.

               

              I only use the OpenGL - Interactive mode.

              • 4. Re: AE CS5 not using all memory and cpu
                artmanphil11 Community Member

                Also, the goal isn't to see that 100% of the CPU and 100% of of RAM is being used. The goal is faster rendering (and other operations). Sometimes greatest performance is achieved when there's "headroom" left over for other activity.

                I disagree. How should unused ressources make anything faster? If I want to render, I don't want to do anything besides rendering!

                100% ram used (afx using installed memory minus os-required-memory) would make my rendering extremely fast, if I am doing a ram-intensive job, same with cpu for cpu-intensive frames.

                 

                20% ram used and 20% cpu used is slower, than 100%. Every 3D-application and even some render-manager-add-ons for after effects handle that and make the renderings way much faster.

                 

                So why doest afterFX have to be the bottleneck because of some sort of "maybe you need some free memory to do something else besides rendering"-agreement? Instead, I would prefer to say "hey afterFX, use all free ressources" - if I would like to do something else, I use the switch "use only xy amount of ram".

                • 5. Re: AE CS5 not using all memory and cpu
                  Dave LaRonde Community Member

                  artmanphil11 wrote:

                   

                  How should unused ressources make anything faster? If I want to render, I don't want to do anything besides rendering!

                  Because there are spots in an AE comp that WILL make use of more RAM and WILL be more processor-intensive.  That's just the way some of the effects and features in AE work.  If you max it out, you're shooting yourself in the foot, plain 'n simple.