Hi,

I rendered a simple grid with material assigned to it in 3000x3000 px resolution. It took 6 min 37 seconds on my computer with very strong Intel i7 processor and 16 GB RAM. Why does it take so long to render such simple geometry? Am I doing something wrong?

I am affraid to think how much will it take to render complicated scene with millions of polygons or particles 8^(

I render the same image in 800x800 resulution in 9 seconds, so it's ok. The difference between this resolution and 3000x3000 render time is huge!!!!!!!!!!!!!!!!!! Why is it so big?

do you have a mantra subdivision active?
hard to tell whats wrong but you can set the verbose to one or two and it will give you some feedback(in the mantra rop).
http://archive.sidefx.com/docs/houdini15.0/props/mantra#statistics [archive.sidefx.com]

whats happening when you use a different material?

Do you mind uploading the file? Kinda of hard to tell what makes it take 6 mins. to render. Rendering a simple grid on my MacPro takes 8 sec for 800x800 and 52sec for 3000x3000.

-b

Grid looks like this

So this image is applied to the grid as a pixel texture, or is this a procedural shader?

It's a shader

OK, I rendered ordinary grey grid in 1000x1000 resolution - render time 6 seconds. Then I did the same in 3000x3000 resolution and the time was 3 minutes. Can anyone advise why the difference in time is so huge? It's only 9 times bigger image and render time is 15 times longer. When there is a shader the difference is even bigger.

Maybe try converting it to rat format (iconvert) and see what results you get. Otherwise submit to sidefx support.

Simple grey grid, headlamp light:
1k * 1k takes 1sec
3k * 3k takes 9sec

Same grid with Env light:
1k * 1k takes 1sec
3k * 3k takes 16sec

in the attached file I have a grid, a camera, a light and a ROP network with a mantra ROP.

rendering in Render View, Preview OFF, Auto update OFF

render micropolygon:
1000x1000 - 2 sec
3000x3000 - 11 sec

render PBR:
1000x1000 - 4 sec
3000x3000 - 21 sec

with principledShader - diffuse texture

render micropolygon:
1000x1000 - 5 sec
3000x3000 - 28 sec

render PBR:
1000x1000 - 5 sec
3000x3000 - 34 sec

if you're getting very different results please submit an example file to support so we can find out what's up.

thanks

If you're rendering in Render View with Preview on, espcially if you have a large number of extra image planes, you may be hitting a known issue where the communication between Mantra and Houdini can become a severe bottleneck. However, if that is what you're hitting, increasing “Update Time” on the IPR toobar from the default of 1 to a larger value, say 10, should probably eliminate the issue, (or you can turn off Preview). It's awfully hard to guess without a HIP file, though.

Artye
Simple grey grid, headlamp light:
1k * 1k takes 1sec
3k * 3k takes 9sec

Same grid with Env light:
1k * 1k takes 1sec
3k * 3k takes 16sec

Hello again. I create default grey grid 3k * 3k with default lighting, I turn off “Preview” and “Auto Update” in Render View. Rendering this grid on my computer with Intel i7 3770K and 16 GB RAM takes 1 minute and 6 seconds instead of 9 seconds. Do you think my computer's processor is 7.3 times slower than processor of Artye's computer? I just don't get it.

mikolaj
Hello again. I create default grey grid 3k * 3k with default lighting, I turn off “Preview” and “Auto Update” in Render View. Rendering this grid on my computer with Intel i7 3770K and 16 GB RAM takes 1 minute and 6 seconds instead of 9 seconds. Do you think my computer's processor is 7.3 times slower than processor of Artye's computer? I just don't get it.

Maybe, though that is quite a long time. If I do:

0) Open Houdini
1) Ctrl+Click on the shelf to place a Grid
2) Ctrl+Click to place a camera
3) Change the camera resolution to 3k*3k
4) Click over to Render View
5) Turn off Preview and Auto Update
6) Click Render

It finishes in 19 seconds on my computer in Houdini 15.5.604 on Windows 7, with an Intel Core i7 3960X and 32 GM RAM, (not that it uses anywhere close that much).

Yes, I do everything like you have described. I don't know what is going on.

Performance of processors (benchmark Cinebench 11.5):
3960X - 10.5
3770K - 7.5

I think that the difference in render time should not be 3x

did you try the tests in the file I posted?

Could be your CPU throttling to avoid overheating ? Maybe check your temperatures ?

OK, sorry. I was doing it a little bit different. I was placing camera directly above the grid and filling frame with the grid.

Now it takes only 35 seconds because grid does not fill the frame.

arctor
did you try the tests in the file I posted?

Hello, yes I have checked it. Here are my results:

render micropolygon:
1000x1000 - 3 sec (your time 2)
3000x3000 - 21 sec (your time 11)

render PBR:
1000x1000 - 8 sec (your time 4)
3000x3000 - 1 min 3 sec (your time 21)


with principledShader - diffuse texture

render micropolygon:
1000x1000 - 7 sec (your time 5)
3000x3000 - 51 sec (your time 28)

render PBR:
1000x1000 - 12 sec (your time 5)
3000x3000 - 1 min 40 sec (your time 34)

mikolaj, over the years, with the renderer Mantra, I can say, that this is normal. Sometimes it works quickly, sometimes not! Raytrace in some tasks slow, Micropoligon running faster all, and if we talk about the PBR, it is also not the fastest. However, often Mantra can handle huge amounts of data without disruption, which gives it a leading quality. Maybe, someday, users will get more faster performance Manta and implementation of GPU rendering. Currently, developers make improvements. When there is improvement - it's good.