17 Replies Latest reply on Mar 19, 2011 10:20 AM by ryan_khoo

    What is the max RAM I should upgrade to ?

    ryan_khoo Level 1

      Hi there,

       

      My system is a 27" iMac i5 2.8 GHz processor with 4gb DDR3 RAM. I am currently now on Snow Leopard OS. My system has 1 processor  and 4 cores.

       

      If I were to be using After Effects CS5, what is the max amount of RAM I should upgrade to ?

       

      Someone told me that the max my system can utilize is 4gb RAM (which means no point in me upgrading the RAM) because I only have 1 processor of 4 cores. Is that correct ? If not, what is the max RAM I should upgrade to ?

       

      Thanks so much, really appreciate a correct answer.

       

      Cheers

        • 1. Re: What is the max RAM I should upgrade to ?
          Mylenium Most Valuable Participant

          The max. RAM in iMacs is 8 or 16 GB, depending which series/ production date. 64bit apps can theoreticalyl address terabytes of RAM (but the OS limiting this), so AE will happily use whatever you can stuff into your iMac.

           

          Mylenium

          1 person found this helpful
          • 2. Re: What is the max RAM I should upgrade to ?
            Wade_Zimmerman Level 6

            As mylenium wrote what you were told about your system is not true your system is 64 bit and 64 bit will take as much RAM as you can give it and After Effects CS 5 can take advantage of more RAM and performs better with more RAM.

             

            Now a graphic card in general will not have as much effect in improving the performance of AE but a graphic card with more VRam will also be of help with open gl features.

             

            So that is also an option your iMacs takes 16 GB of RAM so your answer is 16GB is what you need and when they upgrade the RAM and make it backward compatible that will help as well. So keep your eye to the future. Because 16 GB cards can now be had so when they make them for theMac they might mac them backward compatible.

            • 3. Re: What is the max RAM I should upgrade to ?
              ryan_khoo Level 1

              Thanks Mylenium & Wade,

               

              I have juz checked, my system comes with 2 x 2GB 1333MHz DDR3 SDRAM and there are 2 empty RAM slots.

               

              Since I do not want to throw away the existing RAM, I intend to purchase 2 x 4  GB RAM to make it a total 12 GB RAM. Is such combination allowed ? Must all slots be of the same capacity RAM ?

               

              Assuming I can use (2 x 2 GB) + (2 x 4GB) = 12 GB, is there any particular slot that I must placed the higher capacity 4gb RAM ? Is there any particular arrangement of RAM that must be put into certain slots to maximize the performance ?

               

              Thanks

               

              Kind regards,

              Ryan

              • 4. Re: What is the max RAM I should upgrade to ?
                Wade_Zimmerman Level 6

                that is a good plan it willnwoork quite well.

                 

                you might put the larger carda first

                • 5. Re: What is the max RAM I should upgrade to ?
                  ryan_khoo Level 1

                  Thanks Wade.

                   

                  But sorry, I don't quite get what you meant by "put the larger card first" ?

                   

                  Can elaborate which slot I should put the 4gb piece ?

                   

                  Thanks again

                  • 6. Re: What is the max RAM I should upgrade to ?
                    Wade_Zimmerman Level 6

                    All I meant is you can first load the RAM with the old RAM were it is and the two new cards in the next two slots.

                     

                    If you want to see if there is a difference in the way they perform you you can try putting the two new cards in the first two slots and the two older cards in the last two slots.

                     

                    You have to have matching pairs next to each I believe.

                     

                    I do not think there is a difference.

                    • 7. Re: What is the max RAM I should upgrade to ?
                      Todd_Kopriva Level 8

                      I know that you're asking about a specific computer, but I thought that it might be interesting for you to know what we've found with our testing regarding the payoff of having more RAM.

                       

                      We've found that there isn't much benefit to having more than 8 background rendering processes. Since the amount of installed RAM for each of these should be ~4GB, that suggests that After Effects rendering speed isn't aided much by having more than ~32GB installed. Of course, having a little more so that you can also be running other applications like Premiere Pro and Photoshop makes sense. I would be surprised to see any advantage to having more than 48GB installed in a post-production machine.

                       

                      A lot of folks report that they feel that After Effects CS5 and Premiere Pro CS5 work smoothly with at least 12GB installed. That's what I've got in my desktop computer at work, and I think that it's a good amount, though I occasionally wish for more---especially when I'm working with RED footage. I've got 24GB in my personal computer at home, and I'm quite happy with that.

                      1 person found this helpful
                      • 8. Re: What is the max RAM I should upgrade to ?
                        ryan_khoo Level 1

                        Thanks guys,

                         

                        I have upgraded my RAM to 12GB of DDR3 1333 MHz.

                         

                        Can someone be kind enough let me know if my settings below is correct or whether need to be adjusted:

                         

                        a) Installed RAM : 12 GB

                         

                        b) RAM reserved for other application: 3 GB (Anyone knows why I cannot adjust this to 2 GB ?

                         

                        c) RAM available for AE: 9 GB

                         

                         

                        I also tick the check box on "Render Multiple Frames Simultaneously:

                         

                        d) Installed CPUs (processor cores): 4

                         

                        e) CPU reserved for other Application: 1

                         

                        f) RAM allocation per background CPU: 2 GB (is this correct ?)

                         

                        g) Actual CPUs that will be used: 3

                         

                        Can someone teach me what does item (f) above means ? I changed it from the default 0.75 GB to 2 GB but I dunno why I did it. So it that correct ?

                         

                        Thank you.

                         

                        Cheers

                        • 9. Re: What is the max RAM I should upgrade to ?
                          Todd_Kopriva Level 8

                          This post should answer your questions, especially the second video link near the top of the page:

                          http://forums.adobe.com/thread/543440

                          • 10. Re: What is the max RAM I should upgrade to ?
                            ryan_khoo Level 1

                            Todd_Kopriva wrote:

                             

                            This post should answer your questions, especially the second video link near the top of the page:

                            http://forums.adobe.com/thread/543440

                            Thanks Todd,

                             

                            The answers provided above are for general cases.

                             

                            In particular, I hope to find out, specific to my case of having 12 GB RAM & 4 core whether:

                             

                            (f) RAM allocation per background CPU: 2 GB is too much or high ?

                             

                            (b) Why can't I I select 2 GB for "RAM reserved for other application" in item (b) ?

                             

                            Thanks again, really appreciate your response ...

                             

                            Cheeers

                            • 11. Re: What is the max RAM I should upgrade to ?
                              Todd_Kopriva Level 8

                              > (f) RAM allocation per background CPU: 2 GB is too much or high ?

                               

                              (b) Why can't I I select 2 GB for "RAM reserved for other application" in item (b) ?

                               

                               

                              These questions are addressed in the resources that I pointed you to, but I'll answer here, anyway:

                               

                              (f) It depends on lots of factors. But, here's a generalization: That's a good amount for HD work, too much for SD work, and too little for digital cinema work.

                               

                              (b) Because performance and stability are best when at least a certain fraction of available RAM is not used by After Effects.

                              • 12. Re: What is the max RAM I should upgrade to ?
                                ryan_khoo Level 1

                                Thanks for your reply.

                                 

                                I just rendered a 35 seconds clip and it took 2 hours to render bcos it has a lot of layers.

                                 

                                But when I look at the bottom of the render queue tab when it renders, it says:

                                 

                                "Message: Rendering 1 of 1                RAM: 45% used of 12 GB"

                                 

                                QUESTIONS:

                                 

                                1) Does that mean my setting is not optimized  Only 45% of my 12 GB RAM is being used ?

                                 

                                2) What happened if it goes beyond 100%, the whole thing will crash ?

                                 

                                3) What is the percentage of RAM affected by ? I guess the complexities of layers affects it. But let say if the complexity is constant throughout a 1 min clip, will the percentage of RAM used be constant throughout the 1 min clip ?

                                 

                                4) Could the rendering time takes so long because of the external hdd ? I instruct it to write onto my external Firewire800 HDD.

                                 

                                5) Any idea what causes the bottle neck in my system ? What component is the weakest link ?

                                 

                                Thanks a million & for being so patent with a newbie like me.

                                 

                                Cheers

                                • 13. Re: What is the max RAM I should upgrade to ?
                                  Todd_Kopriva Level 8

                                  If all of your RAM is not being used when rendering a specific composition, then that just means that memory isn't the bottleneck for that specific composition. The rendering of some compositions is memory-intensive, such as when you are working with very large background plates that are several thousands of pixels tall and wide. The rendering of some compositions is bandwidth-intensive (I/O-intensive), such as when you are working with many source files, especially if they are not served by a fast, local, dedicated disk drive. The rendering of some compositions is processor-intensive, such as when using an effect like a glow or blur.

                                   

                                  Quite often, people have lots of RAM and plenty of CPU power, and they cripple themselves by not using multiple fast local drives. Performance is best when you read source files from one drive, write output files to another, and run the programs and OS and caches on another.

                                   

                                  Again, I'll point out that I'm just quoting from materials that I've pointed you to already. You'll do yourself a service if you take the time to actually watch, read, and understand the provided materials. Here's another page that brings together some resources on performance, though it is about both Premiere Pro and After Effects.

                                  • 14. Re: What is the max RAM I should upgrade to ?
                                    mograph_bc

                                    Todd, you wrote:

                                     

                                    "We've found that there isn't much benefit to having more than 8 background rendering processes"

                                     

                                    Is that 8 cores or 8 threads? I have a 12 core which theoretically spawns 24 threads. Should I limit After Effects to 8 cores or 4?

                                    • 15. Re: What is the max RAM I should upgrade to ?
                                      Todd_Kopriva Level 8

                                      >  "We've found that there isn't much benefit to having more than 8 background rendering processes"

                                       

                                      Is that 8 cores or 8 threads? I have a 12 core which theoretically spawns 24 threads. Should I limit After Effects to 8 cores or 4?

                                       

                                      It's processes. You're misusing or misunderstanding the word 'thread'.

                                       

                                      A physical CPU core can appear as two virtual CPUs using hyperthreading. Each CPU (whether virtual or physical) can run at most one process---an instance of the After Effects application. A process can run multiple threads across multiple CPUs.

                                       

                                      When I say that we haven't seen much benefit to having more than 8 background rendering processes, I am referring to eight instances of the After Effects application, each of which is running on a separate processor core (whether virtual or physical).

                                       

                                      So, to answer the last part of your question: 8.

                                      • 16. Re: What is the max RAM I should upgrade to ?
                                        mograph_bc Level 1

                                        Todd, many thanks for the clarification regarding threads/processes.

                                         

                                        I really appreciate your contributions here and on other forums.

                                        • 17. Re: What is the max RAM I should upgrade to ?
                                          ryan_khoo Level 1

                                          Todd_Kopriva wrote:

                                           

                                          If all of your RAM is not being used when rendering a specific composition, then that just means that memory isn't the bottleneck for that specific composition. The rendering of some compositions is memory-intensive, such as when you are working with very large background plates that are several thousands of pixels tall and wide. The rendering of some compositions is bandwidth-intensive (I/O-intensive), such as when you are working with many source files, especially if they are not served by a fast, local, dedicated disk drive. The rendering of some compositions is processor-intensive, such as when using an effect like a glow or blur.

                                           

                                          Quite often, people have lots of RAM and plenty of CPU power, and they cripple themselves by not using multiple fast local drives. Performance is best when you read source files from one drive, write output files to another, and run the programs and OS and caches on another.

                                           

                                          Again, I'll point out that I'm just quoting from materials that I've pointed you to already. You'll do yourself a service if you take the time to actually watch, read, and understand the provided materials. Here's another page that brings together some resources on performance, though it is about both Premiere Pro and After Effects.

                                           

                                          Thanks Todd for the excellent explanation !

                                           

                                          Cheers