Decreasing CPU utilization

[ethan]

We have been noticing that multicore performance tends to decrease over the span of a render. Ie. what starts off with all cores at 100 percent diminishes until only one core is working. We are creating many scenes consisting of only clouds if that figures in. Does anybody know if there is a performance tweak relative to this?

tnx

-ethan

[PG]

I don't think performance actually decreases but the render is split into sectors where one sector is rendered by one core so the last sector is done on one core. I'm hoping this is fixed too but there are several complications in suddenly sending instructions to a new core when it's finished all of its sectors.

[RArcher]

My guess here would be that you are noticing this near the end of a render.  What is happening is that only one core works on each tile at a time.  So when you only have 3 (2 or 1) tiles left in your image then only 3 (2 or 1) cores will still be working.  One thing that you can do is to increase the AA value as that correspondingly will decrease the size of the render tiles.  If you leave the AA value at the default 3, your render tiles are going to be quite large which is where you would notice the cpu falloff while there still may be a large portion of the image still to be rendered.

[ethan]

(One thing that you can do is to increase the AA value as that correspondingly will decrease the size of the render tiles.  If you leave the AA value at the default 3, your render tiles are going to be quite large which is where you would notice the cpu falloff while there still may be a large portion of the image still to be rendered.)


Where is this AA setting you mention - All I can find is Antialiasing

-ethan

[PG]

That's the one.