Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] Bug Reporting => Topic started by: NicolasC on 2018-01-19, 16:58:22

Title: Renderings phases - CPU usage
Post by: NicolasC on 2018-01-19, 16:58:22
Hello,

Not sure if it's a bug or to be expected, but here we go. I've noticed that phases before GI passes (parsing scene, preparing geometry, Computing Sec GI) are pretty slow, then I checked CPU usage ... please check this video capture: https://screencast-o-matic.com/watch/cFVqo7oq5v (https://screencast-o-matic.com/watch/cFVqo7oq5v). I've hidden the VFB on purpose, because of NDA. The scene is illuminated only by an HDRI in environment.

Hardware: bi-Xeon CPU E5-2630 v4 @2.2GHz / 64Go RAM
Software: 3dsmax 2018.4, Corona V1.7.2 / Windows 7 Professionnal x64

Thanks in advance for any help.

Regards.
Title: Re: Renderings phases - CPU usage
Post by: NicolasC on 2018-01-22, 11:46:27
Any thoughts, please ?
Title: Re: Renderings phases - CPU usage
Post by: wilbertvandenbroek on 2018-01-22, 15:01:55
I've got kinda the same performance. First initial phases are slow and don't seem to use all cores. Never looked at it
before because I don't think it is a problem.
Title: Re: Renderings phases - CPU usage
Post by: Frood on 2018-01-22, 17:10:53
There is enough single threaded Max stuff involved at these stages to make the cpu usage look like it is - this is standard, no obvious issue here. It's the reason why most people prefer a fast i7 (or better: "low core count/high frequency" cpu) in a workstation.

In the video we see that Corona GI calc. does not use 100% though, I think you just cannot split GI calc. into any thread count you would like.


Good Luck


Title: Re: Renderings phases - CPU usage
Post by: NicolasC on 2018-01-23, 08:23:36
Hello,

Thanks guys for your comments. Ok, that's a pity then ... I was pretty surprised, hence my posting. As you say, I'll probably suggest we buy single high-frequency single CPUs when we renew our workstations. Bi-Xeons everywhere here so far ! It sure is a good choice for rendernodes, but certainly not for workstations. Anyway, I was just wondering if there were some room for optimization somewhere, but maybe not ;)

Regards.