I am running into a problem that I guess is related to memory usage and number of processors. I’ve spent hours searching the forum but couldn’t find any answers.
Any help would be greately appreciated!!
Description:
I am rendering a scene in both, a dual opteron (2 processors) with 2GB RAM & winXP, and a dual-core dual processor opteron (4 processors) with 2GB RAM & windows 200 Advanced server.
The render on the dual uses 100% of procesor, while the render (same scene) of the quad uses about .05% of the processor. The issue seems to be related to the light cache (Imap is first GI and LCache is the second GI), because whenever I turn off LCache the problem on the quad goes away.
Using performance monitor, I found out that as soon as vRay starts calculating the LCache, the CPU goes down to .05% on the quad proc., and the disk usage goes up to 100%, and hence I assume the bottleneck is being memory-related, and computer is swapping. Funny enough, I still have about 1GB of physical memory free.
I’ve tried playing with the dynamic memory limit, paramters for Lcache, and I even set the number of procesors to 2 (renderers.current.system_numThreads=2 in max) to simulate the dual processor, but could find a solution to the problem. Disk usage still goes up to 100% and procesor down to about 4% as soon as vRay starts calculating the Light Cache.
Has anyone run into this problem before? Any ideas of how to solve this issue?
Turning off “show calc phase” of the light cache, sent the processor up to an average of 60% on the quad-proc.. Now that is funny, I wounder why this is.
I’m am still missing about 40% of processor time. The thing is that now, even though processor is up to 60%, there seems to be no hardrive bootleneck, so I don’t have any ideas why it is that vRay cannot use all 4 CPUs.
I have 4 passes in he light cache.
I also have the cache of maps turned off (I did read all the posts!). Anyway, I am not using too many maps in the scene…
Well, I can’t really say anything else unless you can send us at least some part of the scene to look at to vray@chaosgroup.com; it may be something very specific to your scene.
After much testing, it seems that the problem is related to windows user permissions. Running on the server under Admin solves the problem, so I guess the problem is on our side.
Funny thing is that this happens only with some scenes that use (always) light cache.
I will have our IT guy take a look at this.
Thanks you anyway.