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Mattias
08-27-2005, 07:32 AM
Hi!


I configured SN last night and I noticed that the frames took twice the time to render. Im using two P4 computers and am wondering if Ive done something wrong as Im not gaining any time. For every node that I initialize the rendering time per frame increases. The frames took without SN on my main computer approx. ten seconds to render. With two nodes (on two cpus) they took about 20 seconds each to render. With tre nodes they took 30 seconds each. If I look at the task manager on the second computer it shows that the ram and processor usage is barely none (under 10% cpu and less than 70megs of ram). I set this up according to the video that Matt Gorner provided. Anyone here who had the same problem? What should I do?

Best regards

Mattias

Lightwolf
08-27-2005, 07:48 AM
I guess 10 to 20 seconds per frame doesn't justify rendering across a network. As you found out, the set-up time and time spent for communication between LW and the nodes eats up to much time.
Try a scene where each frame takes longer to render (i.e. a couple of minutes or so). If it is still twice as slow with more machines then you have a problem.
For quick render scenes you could try a third party render manager that can send out a sequence of frames to nodes. In that case network rendering of quick scenes makes sense as well (set-up timeis only required once per sequence of frames).

Cheers,
Mike

Mattias
08-27-2005, 06:03 PM
I tried rendering heavier scenes and saved a few minutes on each compared to the 10 second frames. But it was still strange that the second computer didnt use any ram or processing power. I therefor started the rendernodes on both computers. After a while I powered of the second computer with no difference what so ever on the renderingprocess.

There must be a falty set-up Im using - I must have made an error somewhere..

djlithium
08-29-2005, 07:53 PM
You did.
Remember that the P4 CPUs above 2.8 (some came in lower) are all HT or hyper threaded.
You need to start one node per thread (two per CPU) in order to see the performance gains. Just remember to check how much ram is being consumed by a single threaded LWSN node so that when you run two per CPU you have enough to load the scene twice without causing WinXP to start paging to disc because you now have exceeded your RAM capacity.

StereoMike
08-31-2005, 07:58 AM
Why?What?? errr..?

I'm in the middle of ordering some AMD x2 (dualcore) as rendernodes, so will I have to start two lwsn clients on each system to get full throttle? Can't lwsn handle severall threads on a single machine? Cause that would mean I have to double the RAM, cause there are rendering two scenes on each machine which need double ressources...

Lightwolf
08-31-2005, 08:01 AM
Why?What?? errr..?

I'm in the middle of ordering some AMD x2 (dualcore) as rendernodes, so will I have to start two lwsn clients on each system to get full throttle? Can't lwsn handle severall threads on a single machine? Cause that would mean I have to double the RAM, cause there are rendering two scenes on each machine which need double ressources...
It can use both threads, but that is not as effective as running lwsn twice (depending on the scene also).

Cheers,
Mike

Axis3d
08-31-2005, 02:37 PM
When I am working on my host machine (dual 3.2 Xeon), Lightwave is normally set to 2 or 4 threads. When I do a test frame render, that frame usually renders much faster than the render farm would do it because each cpu on the render farm gets one frame to render (instead of multiple cpu's contributing to render one frame).

I will set my threads in LW back to 1, then do a test render. This more closely resembles the times I will get from my render farm.

tonsofpcs
08-31-2005, 04:28 PM
It can use both threads, but that is not as effective as running lwsn twice (depending on the scene also).Also, make sure you go into the task manager [ctrl+shift+esc] and set each LWSN process' affinity to a different one.