Page 1 of 1

Multithreading - How Many Threads

Posted: Sat May 29, 2021 8:40 am
by arglborps
Just a quicky, but I found that Moho only renders on physical cores, so in my case I've got 8 cores with hyperthreading which does look like 16 cores to the OS, but whether you set multithreading to 8 threads or 16 there's no difference in performance.

Doing a quick check when rendering a scene set to use 16 cores in Activity Monitor, you can see that the hyperthreading virtual cores are basically idle. So if you wonder how many threads you should use, anything beyond the number of physical cores in your machine won't make a difference.

Image

Re: Multithreading - How Many Threads

Posted: Sat May 29, 2021 6:54 pm
by Greenlaw
For me, it doesn't matter. Adding more processors to the list makes Moho appear to render faster but then it stalls for as long as it would take with 4 cores, so I'm hardly seeing any time difference. I wound up resetting it to the default 4 processors.

(No biggie...I've always felt Moho was a pretty quick render, but probably because II have a long history working in 3D which always took a lot longer. Would still like to see this fixed though.)

This behavior was on my Xeon laptop, which is a pretty beefy system with 32GB of RAM. I still need to test Moho 13.5 on my desktop, which is an i7 but it's a decently powerful one with 64GB of RAM.

I use the Crustacea project for my multithreading tests, which I think is a good benchmark project being a heavy render, and every Moho install has it.