VRAY dynamic memory

[BrianKitts]

Anyone have any experience using the dynamic memory range option in Vray for MAX? I'm working on an exterior scene containing a pretty good number of maps, textures, an HDRI, onyx trees, and rpc cars. I'm pretty much tossing in every bell and whistle in to make these images look good.

 

At render I'm crashing due to max breaking my 2 gigs of ram in my machine. Using the dynamic memory seems to be working as a fix. But I want to know if there's a downfall or anything that could cause problems. My guess so far is an increase in rendertime, but is there anything else someone the wiser might know of?

 

thx!

[Christopher Nichols]

Very simplistic answer.... you want to not use dynamic memory as much as possible. basically if you have simple scenes, don't use it, but as soon as you start to run out of memory, try to use it.

 

The drawback is that you are not storing everything in ram, you are are caching stuff on your HD and page to it when needed. While this may seem normal, paging stuff on disk for a raytracing engine is actually very unique, and very hard. Vray's method of doing it works well.

 

Advantage: Can render things that would otherwise not render becasue you would run out of ram.

 

Disadvantage: Is slower since it is accessing stuff from disk. The bigger the scene, the more it has to page the disk, the quicker it will slow down. In this case, a faster HD will mean faster renderings. Also, try to set your dynamic memory as big as possible since it will decrease what you have to store on disk.

[martincg]

or you can try 3gb switch

 

http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx

http://www.eyeonline.com/Web/EyeonWeb/Support/TechFAQ.aspx#15

http://www.chaosgroup.com/forum/phpBB2/viewtopic.php?t=13176&highlight=3gb+switch

 

i think dynamic memory in v-ray is solution for increase speed if in scene are displacement-mapped objects, VRayProxy and VRayFur which are dynamicly loaded

[BrianKitts]

good to hear. thx chris.... always a good source of info, heck I should be thanking you anyway for the great tutorials. I'm slowly getting a better handle on my exterior global illumation. Looking forward to checking out the interiors DVD.

 

(I've attached a progress rendering of the current scene. Minus the rpcs - still a bitta work to do....color balancing etc....)

 

as for the 3g switch I'd have to check with our IT dept before hitting that one, right now we're spec'n new systems at 4gigs so that'll help too. For now the dynamic memory works for a fix.

thx

[Christopher Nichols]

(I've attached a progress rendering of the current scene. Minus the rpcs - still a bitta work to do....color balancing etc....)

 

Looks good... I like the design as well. Maybe a little over filled in the shadows. Are you using and HDR for the sky? Try bringing it down a stop or two (cut the multiplier in half). Shadows could be a little softer... Curbs and pavement look great. You may way to try an add small earth mounds where the trees connect to the grass, may hlep them look not so CG. Either that or a small tuft of taller grass (the kind a weed wacker would miss)... just a suggestion.

[arch alex]

so what is the maximum number we can put ? how can i calculate it ?