View Full Version : RenderGlobals: Memory & Performance options?

10 October 2005, 05:00 AM
I've been having a lot of trouble with my virtual memory getting too high and crashing my (command line or otherwise) render. (MacOSX.4.2, Maya 6)

What do you recommend for the check boxes under Memory and performance? I can't make out whether all on or all off is the more frugal memory option.

Also, is there a way to cap the memory or virtual memory usage? I've got 4.5GB in my box, but I'm coming to learn that doesn't matter at all! My VM hits the limit, and crash! Can I designate somewhere a ceiling so I don't hit it?

So far, my workaround has been to use a long list of command line renders each doing a group of frames to slowly make my way through my sequence. Is this the best way to avoid memory problems? It seems so 1990. Shouldn't my computer know how to manage it's own virtual memory?

One last thing, I've noticed the -mm command to limit memory usage from the command line. Is this helpful? What guidelines would I use if I'm running with 4.5GB ram? Or does it even matter, since the problem is the VM?

Greg :cry:

10 October 2005, 05:21 AM
If you're raytracing and running out of memory, a lower recursion depth will save some RAM, but it'll also slow down your render. Raising the size of your leaf primitives will have a similar effect to lowering your recursion depth.

Tweaking those options can help improve things, but only up to a point. If you're swamping a 4.5 gig machine, you should seriously think about splitting things into more render layers.


10 October 2005, 02:33 PM
I should probably clarify more, I'm using the software renderer and no raytracing or lights.
Since you mentioned render layers, I'll ask;
I understand the idea about compositing and layering, but I feel like on a project like this I'm just out of luck unless I'm not really understanding render layers. In my animation, I have a texture mapped human body that the camera flies through, focusing on a tumor as it moves through the semi-transparent layers of the skin and organs. To my understanding, there isn't really any way to utilize render layers, is there? The only way I can think is to split my body from the background sphere, but that background sphere isn't probably adding a lot of memory stress. The first time I rendered the project, I did split it up quite a bit, but had to fake the composite by using semi-transparency or different transfer controls to put the render back together (in After Effects) to results that weren't as nice as a true fly-through. Is there a better method? I'm attaching a jpg for reference.

10 October 2005, 03:11 PM
I don't know anything about OS-X, but i know that Windows XP can't manage more than 2 GB/application, so even if you have 6 gb of ram, maya or MR will only be able to use 2.

Are you using Depth Map shadows? That can be memory consuming.

Try "Large BSP" as your acceleration method. It takes about 20% longer to render, but it renders... ;)

10 October 2005, 10:38 PM
consider using mental ray

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10 October 2005, 10:38 PM
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