Getting "Building light cache" to use more system resources

[Michael J. Brown]

I've posted this in the hardware/tech forum, but thought I might be able to get some good feedback here too.

 

Is there a way to get the "Building light cache" phase of Vray rendering to utilize all my system's cores/processors?

 

I've noticed that (even though I've got 12 cores) Vray still refuses to run the "Building light cache" phase of the render any faster than it does on my work laptop (which has only 2 cores and 1/5 the power/speed/memory of this system).

[Ismael]

http://forum.asgvis.com/index.php?action=printpage;topic=8371.0

 

"Yes in the light cache Tab inside the V-Ray options you shoul equalize the number of Phases to the same number of threads.

Example:

 

i7 = 8 threads = 8 Num. Phases

Dual Xeón = 16 threads = 16 Num. Phases"

[Michael J. Brown]

Interesting.

 

Thanks, Ismael.

 

However, I've got 12 cores (dual Zeon X5680s), but they are hypertheaded - producing 24 buckets at render time, instead of just one for each core (12).

 

So in this case should I set the number of phases to 12 or 24?

Edited January 21, 2011 by renderhaus

[Ismael]

Michael,

 

Set it to 24.

[Ricardo Eloy]

When you set the Phases to a number that is not a multiple of the number of threads in your computer (for example, set it to 8 instead of the 24 you have), the 16 threads remaining will stay idle, not working on the calcs. That's why you're getting the same performance as in your laptop.

Setting it to a multiple will not only make it use all your threads, but also increase the quality of the calculation. So you could use 24 or 48 (it only goes as high as 64).

[Michael J. Brown]

...So you could use 24 or 48...

 

Very interesting. I've already tried 24 and gotten splendid results. I'll try 48 next and compare.

 

Thanks!