Unused Ram.

[Todd Kopriva]

You asked a similar question recently, and I responded that you should read this page, including the comment at the bottom. I again recommend that. It explains how much RAM can be used for the RAM cache (the RAM in which the frames are stored for RAM preview).

Also, if your concern is the length of the RAM preview, then make sure that the Longer RAM Preview / Faster Rendering slider is all the way to the left, which allocates the most possible memory to the foreground process (which holds the RAM cache). See “Memory & Multiprocessing preferences”.

I think that you might be expecting the wrong thing from RAM previews. You are not going to be able to use RAM previews to quickly create full-resolution, large-frame, full-duration previews of an entire HD movie. If you’re just checking timing, then use a low resolution; if you’re checking the precise appearance of images, then preview a small duration. Make sure that you pre-render as much as possible. Consider using proxies. And so on. Improving performance is not just about finding the right settings for RAM and processor use.

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Todd Kopriva, Adobe Systems Incorporated
putting the ‘T’ back in ‘RTFM’ : After Effects Help on the Web
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If a page of After Effects Help answers your question, please consider rating it. If you have a tip, technique, or link to share—or if there is something that you’d like to see added or improved—please leave a comment.

[Kevin Camp]

hey richie,

i don’t know why with some comps ae will use more ram than with others. but it seems that ae will only use the amount of ram that it needs, and, by the task manager grab, it looks like everything is running at it’s full potential. the cores are max’ed, you’re getting 100% usage, so i assume that ae just doesn’t need all the ram for this render.

if you were seeing the cpu usage down, but ram was max’ed, then adding more ram might help.

if you were seeing that cpu usage was down and ram was not full, then you’d start looking into a faster storage solution and/or drive bus.

but for this render it seems that more processing power is what you need.

i’m sure you know this, but you can always utilize the shift-ram preview option. you can set it up in the time controls palette. for really slow renders you can set it to down sample the resolution and skip frames.

you can also use the region of interest option. it’s at the bottom of the preview window (looks like a rectangle in a rectangle). use it to section off just part of the comp to preview. you can toggle it on and off to go back to full raster.

hd is bringing back the tricks we used when a fast computer was 233-300 mhz.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Richie Tovell]

Thanks Kevin.

Todd did say did say adding more Ram wasn’t going to get me anywhere I just find it worrying, I was about to splash out on 32 gig of Ram then he made me think twice.

I’m trying to ascertain if I really need any extra ram at all (I find this is going against the accepted rule of thumb) the specs that people are currently going for are something like (8 cores – 32 gig of ram).

I know Todd feels like I’m repeating myself here but you have to admit it does seem odd, the recommendations I’ve read on the forums here are that you should install 4 gig per core, here I find my machine would actually only use 1 gig per core (at a push) I could install 8 core’s and run this project quite happily with only 8 gig of ram and still have ram left over!

Do you see what I mean?

[Todd Kopriva]

Installing more RAM will not make your RAM previews longer.

Installing more RAM will allow you to use more RAM per processor for rendering when using Render Multiple Frames Simultaneously.

It’s that simple.

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Todd Kopriva, Adobe Systems Incorporated
putting the ‘T’ back in ‘RTFM’ : After Effects Help on the Web
———————————————————————————————————
If a page of After Effects Help answers your question, please consider rating it. If you have a tip, technique, or link to share—or if there is something that you’d like to see added or improved—please leave a comment.

[Walter Soyka]

In the last thread on this topic, I suggested that you have 2-4 GB per core for multi-processing.

If you don’t have enough RAM to spread among your multi-processing cores, multi-processing becomes slower than a single core processing. What happens is memory starvation: once the computer runs out of RAM, it swaps some RAM out to hard disk to allow one process to work, then when the next process requests RAM, it swaps something else out to disk, and so forth, until something needs a piece of the original, already-swapped RAM; then it swaps something else to load back the original memory from disk.

Having free RAM is a good thing, because it means your computer is still usable. 4GB per core is the upper limit for what you could use, and you may stay well below that.

You mentioned your comp has only 1 layer of footage, so naturally the RAM usage will not be high. Add another couple layers, or another couple hundred (my last project had around 220 layers, and that’s modest by some standards — it’s amazing how quickly they add up), and you will see why I suggest so much RAM. Just to see, I have started re-rendering that project, and my RAM usage is hovering around 17-18 GB. That leaves enough free for me to have Photoshop, Illustrator, Final Cut, Mail, and a web browser open while I render.

Walter Soyka, Principal
Keen Live, Inc.
Presentation, Motion Graphics & Widescreen Design
RenderBreak: A Blog on Innovation in Production