Corona Renderer Forum

Corona Renderer for 3ds Max => [Max] Daily Builds => Topic started by: BVVV on 2021-07-25, 11:40:47

Title: AVX load issue during rendering
Post by: BVVV on 2021-07-25, 11:40:47
After updating Corona 7, the rendered AVX behavior has changed.
7980xe oc 4.5 AVX offset on -5
In Corona 6 and lower versions, the CPU 100% load can correctly identify AVX offset during rendering, and the CPU frequency is maintained at 4.0Ghz, which can well balance the temperature of the CPU after overclocking.
But in Corona 7, the AVX offset is no longer recognized, rendering will always remain at 4.5Ghz, and the CPU temperature has been greatly challenged.
Title: Re: AVX load issue during rendering
Post by: BVVV on 2021-07-25, 11:48:39
Test the situation on the 8280 later. The 8280 is rendered at 2.7Ghz in the lower version. If the offset disappears, it may cause a lot of trouble due to temperature problems.
Title: Re: AVX load issue during rendering
Post by: BVVV on 2021-07-25, 14:15:26
After some tests, it is found that the AVX offset will be invalid in the mini scene, which is a headache for product rendering.
Title: Re: AVX load issue during rendering
Post by: maru on 2021-07-26, 12:06:56
Hi, I would like to understand what exactly you are reporting. Is there some unexpected behavior here? If so, could you please explain what is expected for you and what is the unexpected thing that is currently happening?

In V7, we updated Embree, which now avoids AVX. This may result in higher CPU clocks. The goal of this was better performance, not overheating CPUs. If what you are reporting is that your overclocked CPU is overheating, then I don't think our developers should be blamed for this. :) In such case I would advise disabling the overclocking and making sure that your CPU cooling is good enough.

If you would like to report something else - please do let me know what exactly is happening.
Title: Re: AVX load issue during rendering
Post by: BVVV on 2021-07-26, 12:23:01
Higher CPU clocks means higher temperature.
The frequency that was originally controllable is now uncontrollable. Rendering is more stressful than a single-load CPU, which is not good news for hedt.
BTW...I didn’t complain about the developers, just reported a problem,sorry for misunderstanding
Title: Re: AVX load issue during rendering
Post by: BVVV on 2021-07-26, 12:26:45
In the dual 8280, the absence of AVX load increases the temperature by 4-10 degrees
Title: Re: AVX load issue during rendering
Post by: Juraj on 2021-07-26, 13:11:18
That is natural and expected though. Your CPU is being utilized 6more percent and runs at +200 MHz (at minimum).

You should have faster rendering time. The temperatures are very low anyway, these CPUs can run 90deg just fine.
Title: Re: AVX load issue during rendering
Post by: maru on 2021-07-26, 14:25:25
Higher CPU clocks means higher temperature.
The frequency that was originally controllable is now uncontrollable. Rendering is more stressful than a single-load CPU, which is not good news for hedt.
BTW...I didn’t complain about the developers, just reported a problem,sorry for misunderstanding

I don't think the frequency is uncontrollable, and I don't think this is a problem at all. Software like Corona cannot make your CPU go into some "uncontrollable frequency". Your CPU will process the given tasks at the best possible performance. If you are getting too high temperatures, it is not a software issue.