The numThreads option of Linux V-RayStandalone does not work?

[flat]

The numThreads does not work in RedHat Linux V6.3 (16CPU machine) + V-Ray Standalone, version 3.30.01.

rendering is done as follows:
$ vray.bin -numThreads=2 -sceneFile=bump.vrscene -display=0

If it looks by the top command, the vray.bin thread exceeding two threads will have lanuched.

----------- top command extracted　----------------------------
Swap:    32767M total,        0M used,    32767M free,   765342M cached

   PID USER      PR  NI  VIRT  RES  SHR S   %CPU %MEM    TIME+  COMMAND
167420 s0017     20   0 1421m  77m  26m R    100  0.0   0:31.35 vray.bin
167421 s0017     20   0 1421m  77m  26m R    100  0.0   0:31.40 vray.bin
167438 s0017     20   0 50212 3300 2100 R      1  0.0   0:00.15 top
165239 s0017     20   0 92348 2692 1720 S      0  0.0   0:00.08 sshd
165240 s0017     20   0 53428 5016 2464 S      0  0.0   0:00.35 csh
165477 s0017     20   0 92348 2692 1720 S      0  0.0   0:00.03 sshd
165478 s0017     20   0 53428 5008 2456 S      0  0.0   0:00.39 csh
167365 s0017     20   0 1421m  77m  26m S      0  0.0   0:00.19 vray.bin
167366 s0017     20   0 1421m  77m  26m S      0  0.0   0:00.00 vray.bin
167378 s0017     20   0 1421m  77m  26m S      0  0.0   0:00.00 vray.bin
167379 s0017     20   0 1421m  77m  26m S      0  0.0   0:00.09 vray.bin
                                :
-------------------------------------------------------------------------

44 threads will be lanuched if the ps command checks.

------------------------------------------------------------------------
> ps -efL | grep vray.bin
s0017    105240 134063 105240 52   44 17:40 pts/3    00:00:00 vray.bin -numThreads=2
-sceneFile=teapot.vrscene -display=0
s0017    105240 134063 105241  0   44 17:40 pts/3    00:00:00 vray.bin -numThreads=2
-sceneFile=teapot.vrscene -display=0
------------------------------------------------------------------------

There are not DR and a Spawner demon.

This is correct?

[ydm]

It is absolutely correct.

The numThreads option specifies the maximum number of "ray tracing" threads. You can think of this option as the maximum number of simultaneous buckets rendering your scene, since each bucket is associated with a single ray tracing thread.

Along with the "ray tracing" threads, V-Ray also spawns a number of utility threads, not directly related to ray tracing. What you're observing is not an issue, but rather the expected way for V-Ray to work.

[flat]

understanding.

It is necessary to confine a thread in fixed numbers by huge computer shared by a lot of people.
An environment variable which controls threads also including a utility thread is desired.

Thank you.

[ydm]

Sadly, the total number of threads V-Ray uses internally cannot be a subject of change, since the thread model is already established and heavily optimized in terms of performance.

Anyway, you are guaranteed by the `-numThreads=x` option that no more than x cores of your CPU will be heavily loaded during rendering. Isn't this sufficient for your environment?

[vlado]

We won't be doing that, I'm afraid.

However, you can use the OS tools for setting up processor affinity of the specific application that you are running (Max, Maya, or V-Ray Standalone). For example, Deadline can automatically handle that for you on a render farm.

Best regards,
Vlado

[flat]

I will check the application which limits a thread by the OS side.

Thank you.