Hy there,
we are thinking about growing our business for a large job, rendering stills.
I read that MAX doesn´t support more than 16 cores. If I now render a picture with distributed rendering (DR), is VRay able to use more than 16 CPUs? For example 64, or even more?
The problem is, that our pictures would render at full resolution about 20hours and this we can´t argue with the potential customer.
Does anybody know about the CPU count?
Greetings and thanks in advance…d.
No worries there - with DR you can connect up to ten nodes with one license. Vray will then use all available threads for rendering. It’s fun to see over 40 buckets in your VFB, or i.a.w. 130GHZ working on one image ;).
Best regards,
Michael
This sounds great!
So you mean if we put together 4 Monstermachines with Xeon 55xx and Hyperthreading I get 64 buckets? Would be awesome, but I only trust what I really see 
Thanks for the fast reply!
d.
why stop at 4 when your allowed 10 hehe
The DR machines don’t scale linearly and as you add machines to the job the percentage of speed increase will decrease. In my experience the 8th, 9th, and 10th machine will only increase your speed by a few percentages. Of course it depends on what your rendering so you will get better performance on very difficult scenes.
I have between 100 and 120 buckets in my vfb, so, don’t be afraid ;o)
It would make more sense to use DR for this; V-Ray does not have a limit on the cpu/cores, but you will need a server version of Windows to get more than 16 cores working in the same machine. Further on, performance does not scale that well across many cores when they all start to fight for memory access.
Best regards,
Vlado
well I see 1600 bucketes !
On which machine should the windows server OS being installed? The client (the workstation from which the DR is beeing rendered)?
Is it possible to render a DR-Job with this many buckets from backburner?
thanks for the fast answers!
d.
You only need Windows Server for machines that have more than 16 cores (e.g. a machine with eight quad-core processors). Otherwise you don’t need it and a regular Windows version will be fine, regardless of how many cores take part in the DR rendering.
You can start a DR rendering from backburner; it works in the same way as regular DR (up to 10 machines for DR per V-Ray license, regardless of how many cpus/cores they have).
Best regards,
Vlado
Cool,
this sounds also great! If i´d have a Workstation with 64 CPUs and WinServer2008 for example, I could render with more than 16 cores.
thanks for the answers…d.
Hmmm, I beg to differ. 
Image and the number of cores available under XP64 aside, I’m not currently able to get MAX to run on these processors with hyperthreading enabled. Several other programs run with HT enabled with out issue. These Procs aren’t available to the public yet and my guess is there will be a fix from somebody once they are released. I am getting some impressive rendering times with 12 cores (no HT) however. I’ll post some benches later. I’ve got another computer being dropped off later for testing and to see if we can see what is going on with the HT.
(I may load up Maya on this box to see if it will run with HT on.)
-----showoff-----
Ha!! It would be more of a showoff if I could get MAX to work with that many cores. For now, I’m stuck with HT turned off and only 12 of them going.
On another note… I’ve been MIA from these forums for quite a while and deleted the Benchmark file Percy put together. The link on page one of the thread is dead and I’m not haveing much luck with search. Anyone have this they can send my way? I’m curious to see how this box performs. (wasn’t someone going to put together a newer bench?)
NVM, I found it.
Why would making an irradiance map only use 4 threads when the actual machine has 16 cores and the affinity is checked in all 16 ?
You may have limited the number of threads used by V-Ray; try typing renderers.current.system_numThreads=0 in the MaxScript listener and see if it helps.
Best regards,
Vlado
I resolve this problem simple with dual X5650
rename mentalray.dlz to mentalray.1dlz and used each 24 threads in v-ray
actually i lost mental ray plung in… but… who cares for mental ray?! 
cheers!
Actually you need Windows Server version when you use more than two physical CPUs. Regular Windows versions can utilize all the cores you have, but they are limited by the number of physical CPUs. In regular versions only 2 are supported. However the OS will boot and run just fine but all the 3rd, 4th… physical CPUs will be idle. Considering the cost of Server OS (paid ~850GBP in January), it’s better to go all the way with 2 physical CPU machines. IMHO.
Cheers.