14 Replies Latest reply on Aug 15, 2013 7:35 PM by J2M2012

    RAM preview is not beeing cached – sometimes




      I read through the Adobe recommondations for multiprocessing, I hope I did not miss a crucial point, but here's my problem:


      When multiprocessing for RAM preview is activated, it renders the required frames and plays them as expected. Also the area in the timeline appears green as expected. But in the moment I click somewhere, the part of the timeline goes gray again. When I want to see that part again, I have to start the render for that part all over again – it feels like it was not cached at all. When MP is deactivated, it works as expected – but unfornutaley, my comps benefit a lot from MP and the render goes a lot faster so its really slowing me down to deactivate it. Parts that are cached without MP stay in cache when they are in a part that I re-render with MP later. Then just the new MP rendered parts dissappear.


      Because this behavior just started at some point my opinion was that its kind of a bug. I purged all memory and cache. I uninstalled AE with this clean uninstall tool from Adobe and reinstalled.


      It just happens in some complex comps. So I thought, it might be some option or something that prevents AE from caching mit MP. In one composition, I just have one comp with time remap. When I made a new comp and copy'n'pasted the keyframes, it worked in that manually cloned comp.


      Disabling disk cache does not seem to have any influence on the problem.


      It's strange and hard to reproduce and I was not really able to boil down the conditions where it happens for sure. Any hint what might be the problem would be very appreciated.


      Thanks in advance,




      My system configuration is the following:


      MacBook Pro i7 2.3 GHz, 16GB RAM, 256GB SSD, nVidia GeForce GT 650M

      Mac OS 10.8.4

      After Effects CC –

        • 1. Re: RAM preview is not beeing cached – sometimes
          Todd_Kopriva Level 8

          Show us a screenshot of your Memory & Multiprocessing preferences.


          What other applications do you have running that may be taking up a lot of RAM (web browsers, Photoshop, etc.)?

          • 2. Re: RAM preview is not beeing cached – sometimes
            Timur_C Level 1

            Thanks for the reply!


            As you requested: 

            Screen Shot 2013-07-16 at 17.06.55.pngScreen Shot 2013-07-16 at 17.07.05.png

            Usually I do have some Apps running like Chrome, Apple Mails etc. But it also tried just having AE open and nothing else, which did not help. I do take care that my computer does not use swap, because I know about the bad influence to the performance of swap beeing used. As mentioned in my first post I also tried switching off disk cache which did not help, although the screenshot shows it switched on.


            This is not that much about improving the overall performance, which is just fine – I would like it to stop 'forgetting' the already rendered frames...

            • 3. Re: RAM preview is not beeing cached – sometimes
              Timur_C Level 1

              Here another observation: when I start a preview render and then switch to another program, so that it renders in the background, the preview is also out of cache when I switch back to AE after it finished the render. Although it tells its finished (icon bumping around) then I have to render again.

              • 4. Re: RAM preview is not beeing cached – sometimes
                Rick Gerard Adobe Community Professional & MVP

                Take a look at cpu's used for other applications. It's 0. You have to change that. Make sure that you have at least 1 CPU's for other applications. Try and increase the total CPU's actually used to an even number.


                Also, try turning off MP rendering. While it's better than it was there are still too many problems with plug-ins and cacheing for my taste. It also does not seem to speed up things much on most of my projects.


                Try rendering in the background to disk cache when you are working. When I have disk cache turned on I usually work that way.


                To tell you the truth, most of the time I do not have disk cache turned on and most of the time I do not have MP turned on. AE seems more responsive for the kind of Projects that I do without these features turned on.


                There are some cases where MP will help me. I know exactly when that is. MP does not help at all if you are using Ray-traced rendering. I also very seldom ram preview with all effects, motion blur, and full quality. I just don't have the time. I use ram preview to test motion and timing only, confirm the look with everything turned on for a few key frames, and then render. I've been doing this for so long that I know what things are going to look like and don't have the time to preview them. I'd suggest that you start working that philosophy into your workflow. You'll make more money and get more done in a day.

                • 5. Re: RAM preview is not beeing cached – sometimes
                  Timur_C Level 1

                  Thanks for that reply! Any thanks for the insights in your workflow, I am always curios how people master that stuff. Its just that in the project I am working in the moment I notice a dramatic increased performance using MP and was kind of dissappointed when it just stopped working at some point. I was hoping to save time in the bottom line solving the whatever problem this is (too late now, still I want to have it solved). It bothers me that it's not working and just feels wrong how it behaves...


                  Now to the specific problem:


                  Well, first I thought "cpu's used for other applications: 0" would not have that much effects, since its just using 3 CPU anyway because of ram limitations. But ok, changed it to 4 and the memory per CPU to 1, so its using four CPU's; an even number, did not change anything.


                  I do not use any plugins . Or let's say: not that I know. I use AE of the box and freshly (2 weeks ago) installed.


                  Yes, MP turned off is the way I am working right now but I did not really consider this a resolution. I am also aware of the fact that MP is not faster in all scenarios, but is in mine now. And yes, I also read that MP causes problem sometimes, but I rarely read about unsolvable ones. Why support it in the first place if it would be so? I wouldnt understand if there are usefull features implemented in expensive software my company payed for that are broken, thats all . Or, if there's a bug I would like to help to solve it so it gets more usable.


                  Again, thanks in advance for further help, looking forward to find the solution!

                  • 6. Re: RAM preview is not beeing cached – sometimes
                    TDRonline Level 1

                    My Animations are simple solids moving around and PSD images which I pre-compose. If I turn off MP render and turn off Disk Cache will it affect anything?

                    • 7. Re: RAM preview is not beeing cached – sometimes
                      Rick Gerard Adobe Community Professional & MVP

                      TDRonline, first of all make sure your AE is up to date. Second, Turning off disk cache will disable rendering in the background and may slow down some workflow's but it will also solve the problem of random frames hanging on when you render. This is improved with the latest update.


                      Turning off MP may or may not slow down your ram previews or renders. If you are having very slow renders and MP is turned on the first thing to do is to try turning it off. Render multiple frames simultaneously will not work if you are using AE's Ray-traced rendering or if you are using any temporal effects that must process a frame at a time. Unless I specifically know that my project will render faster with MP turned on I keep it off. This means it's off 90% of the time.

                      • 8. Re: RAM preview is not beeing cached – sometimes
                        TDRonline Level 1

                        Thank you,

                        This helped a whole lot, now I'm not having random lag when rendering. Seems to have done the trick.

                        • 9. Re: RAM preview is not beeing cached – sometimes
                          Timur_C Level 1

                          So, that does not help in my case at all and TDRonline's problem also does not seem to be connected to my problem. Why not open another question for another problem?


                          Any ideas for my original problem? Is it a bug that should be reported? Did it occur to anyone else? Any strategies to avoid it?


                          Thanks in advance!

                          • 10. Re: RAM preview is not beeing cached – sometimes
                            Todd_Kopriva Level 8

                            > Is it a bug that should be reported?


                            Any time that you find yourself asking that question, the answer is "yes":


                            • 11. Re: RAM preview is not beeing cached – sometimes

                              I was having this issue, and I seem to have fixed it by emptying both the CC disk cache data and my AE CS6 data. Hope this helps.

                              • 12. Re: RAM preview is not beeing cached – sometimes

                                Hi Timur,


                                I also had the exact same problem, but emptying both the CC disk Cache and (in my case) the CS5.5 one, and restarting AE CC solved it.

                                I don't know for how long, but for now it works.


                                So thanks to ekreidler !



                                • 13. Re: RAM preview is not beeing cached – sometimes
                                  J2M2012 Level 1

                                  Well, sorry to report that it didn't last long.

                                  It worked fine for about 20mn, and then the problem started again, only differently : Now when I stop a Ram preview playback, some frames stay cached (with the green bar), and others don't. It also seems completely random.

                                  Also, during those 20mn, I stayed in the same comp, after rebooting, and without any other app running.

                                  I'll have to revert to CS5.5 (in which Ram Preview works normally) as long as this issue isn't officially adressed.


                                  Specs :

                                  Mac Pro 12-Core 2010 / 48Gb Ram / Mac Os 10.7.5

                                  • 14. Re: RAM preview is not beeing cached – sometimes
                                    J2M2012 Level 1

                                    I have more details :

                                    Actually, the frames that stay cached (with the green bar) after playback are not random at all : They're the frames I previewed while scrolling manually through the timeline. But all the other frames unread while scrolling lose the green bar once the preview playback is stopped.

                                    Also, the problem only occurs when MP is turned on. With MP off, all the frames stay cached normally.


                                    AE CS5.5, tested with the same project on the same machine, with the same MP prefs, doesn't have any problem, and keeps all the previewed frames cached after playback, just as it should.