Render Times and Texture Memory Consumption

RA

Good Afternoon,

My question concerns reducing the amount of memory consumption allocated to Textures while rendering.

I completed my first IRay animation render with 2 characters moving.  The 5.5 second .avi took almost four hours to render.

I am running Win10 on a machine I build myself [Ryzen 7, single GTX 1080].

For Render Settings, my environment is set to Infinite Sphere. All other environment settings are default. I did enable Spectral Rendering and selected Natural. General settings Full HD. Optimization Settings have Quality turned off and Max Samples at 144.  Max seconds at 600. I am rendering with Nvidia Iray selected and under advanced I have GPU selected in both panes.  Optix is not enabled.  priority is Speed.  In the viewport I do have Iray selected.  I have one distant light, no background, HDRI or other lighting.

I rendered a still image with a single V7 character and found that Textures were consuming 1.6 Gb.  I added another character and the Textures increased to 1.8 Gb.  I loaded my full scene, 1 building, 2 sidewalks, 2 vehicles, 2 characters.  Texture Memory consumption jumped to 4.67 Gb.  (I have 8Gb on my graphics). All other memory consumption adds up to Mbs. [Attached is an image of my scene.]

My question is will shrinking textures either manually or with a product like Scene Optimizer significantly (as in by half or even one third) reduce the amount of Texture Memory consumption during rendering?  If so, will this speed up my renders?

Any advice or observations are appreciated.

RA

chris-2599934

RA said:

The 5.5 second .avi took almost four hours to render.

What frame rate is your animation running at? The Daz default is 30fps, so your 5.5 second animation needed 165 images rendered - each one apparently taking about 1.5 minutes. I reckon that's pretty quick!

If (as in your case) the total amount of texture memory is less than the capacity of your card, you're good. I don't think there's a lot of gain from shrinking it further.

PS. Unlike 3delight, Iray tends to get quicker when you add more light. It's rendering the shadowy areas that takes all the time.

RA

chris-2599934 said:

RA said:

The 5.5 second .avi took almost four hours to render.

What frame rate is your animation running at? The Daz default is 30fps, so your 5.5 second animation needed 165 images rendered - each one apparently taking about 1.5 minutes. I reckon that's pretty quick!

If (as in your case) the total amount of texture memory is less than the capacity of your card, you're good. I don't think there's a lot of gain from shrinking it further.

PS. Unlike 3delight, Iray tends to get quicker when you add more light. It's rendering the shadowy areas that takes all the time.

Chris,  thanks for responding.  I had no idea Iray speeds up when you add more light.  I will add a couple of lights and check the render time. Yes, I am rendering at 30fps. Would dropping to 24fps help, or would the quality trade-off be too drastic?  

Thanks again,

RA

chris-2599934

I would suggest doing test renders of a single frame of your animation (renderd as a still image), playing with light levels quality parameters, etc. till you get it rendering in a time frame you like. Then you can use those same settings for your animation. I'm not qualified to say what effect a lower frame rate would have - you'll just have to try it and see.

I've not done much animation myself, but my impression is that it simply is a time-consuming process (unless you have mega bucks to throw at professional level hardware). Set your animation up and let it render overnight or while you're at work. Heck, some of us have to do that with still images!

RA

Chris, thanks. I'll work with the still images first!

RA

fastbike1

@RA "My question is will shrinking textures either manually or with a product like Scene Optimizer significantly (as in by half or even one third) reduce the amount of Texture Memory consumption during rendering?  If so, will this speed up my renders?"

Memory consumption will be reduced. That is the objective of Scene Optimizer. Lower texture memory requirements will reduce the time it takes for the scene to load in the card (before it starts rendering). How much reduction is hard is hard to predict, but is probably a tertiary impact on render time at best.

RA

fastbike1 said:

@RA "My question is will shrinking textures either manually or with a product like Scene Optimizer significantly (as in by half or even one third) reduce the amount of Texture Memory consumption during rendering?  If so, will this speed up my renders?"

Memory consumption will be reduced. That is the objective of Scene Optimizer. Lower texture memory requirements will reduce the time it takes for the scene to load in the card (before it starts rendering). How much reduction is hard is hard to predict, but is probably a tertiary impact on render time at best.

Thanks for responding, @fastbike1.  I did drop the resolution in render settings to 720 p and halved my render time. Maybe I'll play around with some other settings. Does IRay load the scene for each frame?

 

Thanks,

 

RA

fastbike1

@RA "Does IRay load the scene for each frame?"

I don't do animation but I suspect it does if/when the frame substantially changes or if the preceding frame is closed.

For still frames, if a frame is cancelled for any reason but left open, the next render of the "same" scene will be begin iterating much faster than the initial load.