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Lux only using half of the CPU

Posted: Thu Jun 11, 2020 7:22 pm
by steven850
Hi, installed the luxcore blender add on, running 2.83 stable, tried the lux build from the website as well as the latest build from git.

When rendering its only using half of my CPU. I have a 3990x (single Numa node) running windows 10 enterprise. I also tried setting the threads manually to 128 but it still only uses half of the CPU. Cycles uses the full 100%.

Anyone know whats going on here?

Thanks,
Steven

Re: Lux only using half of the CPU

Posted: Thu Jun 11, 2020 10:03 pm
by Dade
steven850 wrote: Thu Jun 11, 2020 7:22 pm Hi, installed the luxcore blender add on, running 2.83 stable, tried the lux build from the website as well as the latest build from git.

When rendering its only using half of my CPU. I have a 3990x (single Numa node) running windows 10 enterprise. I also tried setting the threads manually to 128 but it still only uses half of the CPU. Cycles uses the full 100%.

Anyone know whats going on here?
Yes, it is a Windows limitation about having more than 64 threads. Running more threads require some specific code, the support has been added in v2.4 so it should work fine if you use an automatic build from the latest sources: viewtopic.php?f=9&t=736

Re: Lux only using half of the CPU

Posted: Fri Jun 12, 2020 9:05 am
by juangea
TBH the first thing I ended doing when I acquired our 2990WX was to install linux, Windows handles those CPU horribly wrong, you get a lot more performance and way less problems with linux in these cpu’s, so if you have the chance to have a linux SSD for rendering, test it and you will see what I mean :)