Join Todd Kopriva for an in-depth discussion in this video Optimizing CPUs, part of After Effects and Premiere Pro: Optimizing Performance (2011).
One somewhat obvious component of optimizing for performance, is having fast CPUs, fast processors. A somewhat less obvious component of optimizing for performance, is having multiple fast CPUs. Both Premier Pro and After Effects are multi-threaded applications, meaning that each application can spawn multiple threads, each of which can run on separate processors. So that if you have, for example, eight processors or eight CPUs, in your computer system, all eight of them can be used at once. As we can see here, in the Windows Task Manager, the computer system that I'm currently using has eight CPUs.
And they're all currently doing very little. If we start playback in our sequence in Premiere Pro, we can see that all eight CPUs are used. Many of them at full capacity. And as the sequence reaches a point where the processing is a little less demanding because there is only one track, the CPU usage falls off.
And then as the playback ends, the CPUs will go back into a quiescent state. So you don't have to really do anything at all to take maximum use of all of your CPUs. Premiere Pro will spread all of the processing out by using multiple threads as much as possible. Now let's go back to the beginning of the sequence, and change the project settings. To use the GPU also, we did have this set to Mercury Playback Engine Software only, because I have an NVidia card installed in this computer, that Premier Pro can use for code acceleration. I can check Mercury Playback Engine GPU acceleration.
Click OK. Go ahead and delete the preview files that are associated with the other renderer. And now, if I press Play, all of the CPUs are still used, but not quite at full capacity. And that's because the CPU process some things, but the processing of many things such as the processing of the color correction effects that I have on here, as well as the blending operations, are handled by the GPU.
And as the sequence ends, CPU usage will fall back to zero, or near zero. So for Premiere Pro for optimum performance, you want to have multiple fast CPUs, the more CPUs the better. And ideally also install the GPU, specifically in an NVidia card that can provide the CUDA processing features. Now, let's look at how After Effects can use multiple CPUs. I'll close Premier Pro, and now we're in After Effects.
So, within After Effects, we'll go to this composition and press the Spacebar to do a standard preview, not a RAM preview. And we'll see, that all of the CPUs are used in very much the way we saw them all used in Premier Pro. As the multithreaded After Effects application spreads the processing out to all of the processors. And I'll hit Spacebar again to pause the playback.
After Effects also has the ability to use multiple background processors to render multiple frames simultaneously. Let's see how that works. Let's go to the Preferences, Edit > > Preferences Memory and Multi-processing. Here we have Render Multiple Frames simultaneously turned on. It is not turned on by default. After Effects is telling us that we have eight CPUs installed. We actually have four physical CPUs, but because of hyperthreading, the operating system is able to use each CPU as if it's two.
We've told After Effects to reserve two CPUs for other applications. So that even if we had enough RAM installed in the system, to feed all eight of the CPUs for After Effects, After Effects would still only use a total of six. That way we can run other things in the background, such as Photoshop or a Web Browswer, and not have After Effects and the other applications fighting over resources. I'll Click OK. And start Orion preview. And in the Info panel we see that the background processes are currently loading the project, so they can do the work on them as well.
Then once those projects have been loaded by the background processes, they will work together, so that they process multiple frames of the composition at the same time. And you see again, that the CPU usage is very high for every CPU in the system. And several frames are being rendered at once. And then we get a real time playback, using Rain Preview. I'll pause the playback. And close the Task Manager.
For either After Effects, or Premiere Pro, when you're making a buying decision regarding processors, consider both the speed of a processor and the number of processors you can get. Both After Effects and Premier Pro will take advantage of all of the processors that you have in your system.
- Planning your work, updating, and auto-saving
- Learning and customizing keyboard shortcuts
- Optimizing hard disks and CPUs
- GPU: CUDA and OpenGL
- Using "Render Multiple Frames Simultaneously" multiprocessing
- Pre-rendering and proxies in After Effects
- Lowering resolution for previews