Le 2025-10-05 à 20:04, Clarence1898 a écrit :
> "Kenneth" <kdw### [at] gmailcom> wrote:
>> "Clarence1898" <dle### [at] comcastnet> wrote:
>>> "Maetes" <nomail@nomail> wrote:
>>>
>>> Still I would like to know how everyone does their rendering.
>>
>> [running Windows 10]
>>
>> Hi!
>>
>> I have been rendering POV-ray animations for many years, all the way back to
>> Windows 98 days, when machines had only single cores. Now I have a Corei7
>> machine with 8 cores/16 threads. (Quite an improvement, ha.)
>>
>> To be honest, I was not even aware that multiple instances of the app could be
>> run *successfully*...that is, with an overall speed improvement for a scene or
>> an animation...since it has always been my understanding that even a single
>> instance of POV-ray uses most of the resources of the entire machine for
>> rendering. At least, that's the way it used to be on my various single-core
>> machines through the years. (And AFAIU, initially *parsing* a scene uses only
>> one thread, regardless of how many threads are available.)
>>
>> But the faster results of your multi-instance use are a real surprise! I will
>> have to give that a try, to see what the speed improvement might be for my own
>> animations.
>>
>> There remains a question, though: When running multiple instances of the app on
>> multi core/multi thread machines, does each instance's scene parsing use it's
>> *own* single thread to do so? I.e., with 3 instances running (for example), are
>> there now 3 threads dedicated to parsing the (3) scenes? Or just one thread as
>> is typical-- split up between the 3 instances?
> 
> When I started using multiprocessors I noticed the performance advantage of
> multiple instances, but it was on a much smaller scale.  It was only with more
> and faster processors that it became noticeable.  With my first quad-core system
> the difference was about 15% improvement.  With a 20 cpu i9 the difference is up
> to 60%.  For more complex scenes the smaller the difference, but still
> noticeable.
> 
> As I understand it, each instance is completely independent from the others.
> Each instance will have its own threads.
> 
> 

When using POV-Ray version 3.6 and earlier, you couldn't use more than a 
single core/thread. So, back then, using several instances was the only 
way to use all of your cores on a multi-core system.
The main feature of version 3.7, and the reason it was developed, is the 
ability to use all the cores of modern CPUs.

Post a reply to this message