100% cpu in IPR usage in daily?

[Stefan-L]

for some reason i get often 100% cpu usage in IPR render, even though i set the IPR to not use all threads.

any idea?
this is new for me, i use latest v13 daily

this means i can hardly edit any while IPR is running

thanks
for info/help
Stefan

[TomG]

What OS, and what hardware, please? And can you share screengrabs of the settings, so we can double check what you have set :) Thanks!

[Stefan-L]

win10, dual xeon 56 core, c4d 2024.5

default settings, denoiser for IPR off

also if i reduce the cpu usage  settings for IPR it doesnt improve

i didn t have this in 12, but now in almost any bigger scene, i cannot even stop the the ipr render or close the vfb window(only after many tries)

the extreme cpu usage problem is ONLY when rendering IPR, not when rendering final images.

[Stefan-L]

ok maybe i found it; the default -1 setting (one thread less than all possible threads) seem not to work anymore, also not -2,-3,-4...

what does work it seems is set the actual thread number, so i used 24 threads and now ipr usage is like expected and the gui doesnt stall anymore.

[Stefan-L]

sadly i must say it isnt solved, the problem comes back after a time:

1) even though i set cpu thread usage to 12(on a 56thread pc) it often uses 99% cpu power, it seems to ignore this setting
i also had the case where it did ignore the max IR resolution which i have at 1600px, still it did render more than 17xxpx

it seems the settings are party ignored, it is not related to once scene but many new and older, most time faster a time of rendering,
it is ONLY in IPR, fial render works fine.

somehow i have the feeling v13 has a very aggressive threading for the pr, this is counter productive. today i had to force kill a project, loosing 20 min of work, and not even that worked, the only way was to force restart the whole PC.

i hope you can solve it, Corona is great, but this problem is quite a pain.

[Ales]

Hey, the issue with IR threads limit not working should be resolved in the latest RC2.

[Stefan-L]

thanks Ales,

i load this right away, RC2 seem to have some very good fixes!

[katzenwaffe]

Sure this is fixed for Mac version in RC2?
Still has 100& CPU on IPR.

[TomG]

Are you sure Corona is not set to not use all threads in IR? In which case, it should be using 100% :)  Can you share a screengrab of that setting please?

[katzenwaffe]

Settings are correct?

[TomG]

Yep, that looks right. Do you experience lag or slowdown as mentioned earlier? (If not, then the reporting system saying the CPU is 100% in use is not a problem - only if it's having an impact on responsiveness is it an issue). What OS are you using, and which version of Corona? Do you still see 100% usage (and lag) with threads set to something like -4? And what if you use the positive number as mentioned in an earlier post (so if you have 32 threads, setting "31" in there)? Thanks in advance for the extra info!

[katzenwaffe]

I experience such lag whole system freezes during IPR rendering. Has not been the case before.
Changing thread-numbers seem to fix nothing?

Sonoma 14.5 (23F79)
Version • 12 Update 1 (Release Candidate 2)
Build timestamp • Nov 14 2024 02:38:57
Cinema version • 2025.1.1 Cinema 4D

[TomG]

Why are you using an RC of Update 1, since it is out officially? Definitely be sure to be using the final official release :) You could also try the latest daily at https://forum.corona-renderer.com/index.php?topic=43211.msg230037#msg230037 - let us know if either of those builds still give you issues, as changing the thread numbers should make a significant difference (make it so Corona only gets 1 thread, ensure that things are a lot slower, then we know the number changes are working :) ).

[katzenwaffe]

Well, my guess it's due to pure incompetence or post traumatic retardness. Will use latest and try it 🫣.
Sorry bothering you guys with stupid questions when I apparantly should check obvious stuff first.

[TomG]

Oh, not a stupid question, as it may still happen with the official release - but is worth running it juuuuuust to be sure :) Eliminates some small possibilities on the cause if we know for sure. Anyway, no question is ever a stupid question (except the unasked one, as then it never gets answered!). Keep on with the feedback and questions, please!