Too many cores (processors) for Rhino


#1

I ran Rhino on a 32 core box … it did not start … in windows I dropped the cores down to 16 and it worked , anyone experience this or know why it affects Rhino running?


(John Brock) #2

I know there is a System Requirements limit on no more than 63 cores.
By chance do you have 32 dual-core processors?


(Menno Deij - van Rijswijk) #3

Could also be due to hyperthreading.


#4

Why?


#5

I use a dual core xeon with 32 threads - 2 cpu, each 8 cores, HT. Rhino works like known.


#6

They are threaded since I have 8x4 dual threaded for 64 logical threads
why does hyper threading make it throw up?


(Menno Deij - van Rijswijk) #7

Hyperthreading makes on core look like two to Windows. Hyperthreading can normally be disabled in the BIOS.


#8

So far I know for rendering disabling HT cause longer render times. If I understand right HT helps to better user the hardware.


#9

It’s a licensing limitation.


(Menno Deij - van Rijswijk) #10

Sure, but if you have 32 cores and Rhino does not work with 64 HT-doubled cores, I think you are having “luxury problems” and can safely disable HT.

As, the OP said, reducing the #cores in Windows solved the problem.


#11

My question was directed more to that strange number 63 and the logic behind it.

Since you normally don’t add cores by single numbers but more like 8 of 12 as in hyperthreaded quad or six core CPUs, that limit is effectively about 56 cores.

Then there is the question of why limiting the number of cores at all because
a) Rhino doesn’t generally make good use of multiple cores
b) Desktop windows supports only one or two physical CPUs, AFAIK
c) if you wanted to prevent Rhino from running on servers, it’s probably simpler to just check the windows version because
d) if you are running a server, it shouldn’t be a problem to just sandbox Rhino and limit the number of visible cores there.