Dual Processor Multithreading Optimizing

[Eyenovation]

I read somewhere in a tutorial that the multithreading should be set to the same amount of processors I have for optimum performance. Is this true?

(I have the dual 1.42)

http://www.eyenovation.com/forums/multithreading.jpg

Thanks!

[Ge4-ce]

Yes, that is the general rule.. however, you can perform your own test!

Perform a render and look at how fast it goes..

try 1, 2 4 and 8 threads

You can actually see the difference when you choose the option "show rendering in progress"

the more threads you have, the more pencils are drawing your picture..

you can compare it like that.. every thread is a new person that helps you completing the image..

If you have 2 processors, each can perform his part of the picture.

however, things highly depend on rendersettings, plugins etc.. experimenting is the only way..

[ArneK]

I have a dual 1Gz G4 myself, and I did a test on a raytracing scene with the following results:

- 1 thread 3 min 59 sec
- 2 threads 2 min 31 sec
- 4 threads 2min 7 sec
- 8 threads 2 min 8 sec

This differs between how your scenes are, so it is better to make a test before you render large animations sequences. In this example 4 threads was actually better than 8 threads.

[drclare]

I have a dual 800MHz and generally 4 threads work fastest for me. I did test initially when i started using lightwave, and 4 turned out to bit quite a bit faster than two, and very slightly faster than 8 threads. I just leave it a 4 now.

[Jimzip]

Same here.
I have a dual 1.25GHz G4 and four threads seems to be faster than two, and just a bit faster than eight. Curious.
Just don't use multithreading with hypervoxels. Ugh.. (Slows down a LOT)


Jimzip :D

[Eyenovation]

Originally posted by Jimzip
Just don't use multithreading with hypervoxels. Ugh.. (Slows down a LOT)


What is hypervoxel? I am a total newbie. I have not gotten to that part yet in the manual.

[Ge4-ce]

Originally posted by Eyenovation
What is hypervoxel? I am a total newbie. I have not gotten to that part yet in the manual.


Mwwooeee haa haa haa.. you will be.... :eek: .... you will be....

No serious..

Hypervoxels is a the "engine" If I may call it, to visualise particles!

You can use, animatie, particles to make explosions, fluids, smoke etc,..

the particle part takes care of the motion (better: you take care of the motion of the particles) hypervoxels takes care of the "how does 1 particle look like" comparable with your surface editor, but with slightly different options..

Jimzip!!: question: did you ever test this conserning:

hypervoxels volumetric, sprite or surface?

I mean, maybe multithreading goes slower only when using volumetric..

I don't have a dual Processor so I can't test it..

Maybe this is worth a new thread?

[Ge4-ce]

yeah, I will post a new thread about that..