Inconsistant render times

[solidwave]

Hi
I am experiencing a strange varition in render times depending on which computer I use. I own two quadcore machines and a dualcore laptop. My quadcores render with identical times using Fprime, however if I render with Kray one is over 3times faster than the other! My much slower dualcore laptop renders faster than one of my quadcore machines. I am finding it very baffling and can only guess that one quadcore has a strange setup which means it is not optimised for Kray use. If any one knows anything about this or can offer any information It would be much appreciated!

[jure]

That is strange. Are you using exactly the same scene?

What are other computer specifications?

[solidwave]

I am rendering an animation. I have tried rendering the same frame on all machines, one zaps through in 3 mins 30 and the other takes 12.20. My dual core laptop take 7mins 40!

Specs of machines are:


Slow quad core one: 4 x2.4ghz 4GB ram 32 bit win xp ATI FIRE GL 7200 graphics rendertime 12.20

Fast quad core: 4 x 2.4Ghz overclocked to 3.2Ghz 6Gb Ram 64 bit win XP ATI Radeon 3800 Graphics rendertime 3.30

Laptop: 2 x 2 Ghz 1.5Gb Ramwin XP 32bit. rendertime 7.40

[jure]

Hmm I can't see anything strange from your PC spec.

Could you share scene so I can test it on my quad?

[solidwave]

It is almost as if it is only using one core. Is there a way ofchecking if all 4 threads are working??

[except]

Multithreading settings? Detection?

[solidwave]

is that a command for the tailer commands?

[florian]

is that a command for the tailer commands?

I think Kray uses the LW settings so you might want to check in the render globals.

Florian

[solidwave]

Threads are showing as 4 and multithreading in Render globals is also set on 4.

I tried increasing octree depth on the slow Quad core. It was at the default 20, I increased it to 30 this brought the render time down from 12mins to 7mins 30!
This is better, although it should be more like 4mins 30.

I then tried increasing the octree to 35 but Lightwave crashed at setup. It is completely baffling, I can not understand why there should be such a difference.

[phile_forum]

Check the slow machine is definitely idling before you start the render (the %cpu use in the Task Manager). If it doesn't show close to zero, then you have something else running that is eating up your processor's time. Could be a rogue service or process or something.

[solidwave]

Task manager shows 0% at idle.

I am now very confused, I tried rebooting and now with the octree at 30 it takes 13minutes to render a frame and I have not changed any settings??!! it really seems to be very random.

[jure]

Is this only happening in one particular scene or are you noticing slowdowns in all your scenes?

Can you try rendering benchmark scene from here: http://www.kraytracing.com/forum/viewto ... =3894#3894

[solidwave]

it seems to be a problem with this scene. I rendered the benchmark and got the following results:

Slow Quadcore: 3min 55
Fast Quad: 3min 03
Dualcore laptop: 10min 55

Fortuantely this shows that both of my Quadcores are running as they should do, however it is very odd that the same scene can render with such a variation in rendertimes on two fairly similar machines.

[jure]

Indeed, you should send me a scene and I will test it.

[jure]

Your scene renders in 3min 12sec on my quad.

Can you do one more thing please:
add logfile 'kray_log.txt' from the header commands list and render. Then send me the log file so I can check where is slowdown happening.