V-Ray CPU Core Limit

[drew_almighty]

I am trying to render with both full V-Ray and RT and noticing that while I have 48 cores, only 28 of them are being used for rendering. Is this limit built into the V-Ray software?

[Dariusz Makowski (Dadal)]

Try increasing ur bundle size in vray. Does vray uses all cores in production render?

[drew_almighty]

No, it uses 28 regardless of production or active shade

[vlado]

Currently V-Ray can use up to 256 cores. If you look at the V-Ray log file, how many threads is it creating for rendering?

Best regards,
Vlado

[Dariusz Makowski (Dadal)]

Oh thats strange... now I dont usually advise that but does mental ray or scanline use all cores? It could be related to windows envi being set up to lower cores

[drew_almighty]

Vlado,

Here is what I believe to be the applicable section of the log file:
[2014/Feb/24|10:37:13] Sampling displacement maps.
[2014/Feb/24|10:37:13] Updating render lights
[2014/Feb/24|10:37:13] Setting up 48 thread(s)
[2014/Feb/24|10:37:13] Threads completed
[2014/Feb/24|10:37:13] Setting up 48 thread(s)
[2014/Feb/24|10:37:13] Threads completed
[2014/Feb/24|10:37:13] Updating atmospheric effects.
[2014/Feb/24|10:37:13] Updating render effects.
[2014/Feb/24|10:37:13] Scene setup: 19.8 s
[2014/Feb/24|10:37:13] Compiling render instances geometry.
[2014/Feb/24|10:37:15] Compiling lights geometry.
[2014/Feb/24|10:37:15] Preparing ray server.
[2014/Feb/24|10:37:15] Creating and initializing 48 thread(s).

This is the log I got after a rendering this morning that again only used 28 cores.
Mental Ray is using the same 28 cores.

[drew_almighty]

Just did a screen grab using DR to see the buckets, and there appear to be 48 buckets. Not sure why both the task manager and the resource monitor are reporting only 58% CPU usage and showing 20 cores not being used.

[vlado]

What OS do you have by the way?

Best regards,
Vlado

[drew_almighty]

Windows 7 Professional SP1 64 bit

[vlado]

I'm not entirely sure about this, but I think the Pro version has a limit of 32 cores per application, whereas the Server version can go up to 64. But as I said, I'm not sure. Is there any application that is able to use the full 48 cores?

Best regards,
Vlado

[drew_almighty]

From what I can find on the Microsoft site, it seems like it should support 48 cores easily...

"PCs with multi-core processors:
Windows 7 was designed to work with today's multi-core processors. All 32-bit versions of Windows 7 can support up to 32 processor cores, while 64‑bit versions can support up to 256 processor cores.

PCs with multiple processors (CPUs):
Commercial servers, workstations, and other high-end PCs may have more than one physical processor. Windows 7 Professional, Enterprise, and Ultimate allow for two physical processors, providing the best performance on these computers. Windows 7Starter, Home Basic, and Home Premium will recognize only one physical processor."

I will try and test other software to see if it behaves the same.

[Dariusz Makowski (Dadal)]

Can u go to

Start>Computer>Properties>Advance system settings>Environment variables> do you have variable NUMBER_OF_PROCESSORS and as argument 48?

[Rhys]

Having something similar myself, however when max starts up on one of the 48 core nodes, it loads and only has 24 cores active then have to active all the rest of the cores by set infinity how can I get this to load up and use all 48?

[Rhys]

Picked up answer in other thread , used renderers.current.system_numThreads=48 will that save for every season or will I have to redo it everytime?

Actually didn't work opps!

[svetlozar.draganov]

Picked up answer in other thread , used renderers.current.system_numThreads=48 will that save for every season or will I have to redo it everytime?

Actually didn't work opps!

It will be saved into max-file, so there is no need to redo it for scenes that already have it but you should set it up for new ones.