Corona is not using 100% of CPU #2

[draxdamax]

Hi,

I am not sure if this is a bug but is this normal?:

I know I don't have enough ram but this keeps happening with the daily builds even with small scenes and even with scenes I rendered normally with the previous versions.

It is possible there is a "memory leak" or something dodgy with the new embree implementation?

[FrostKiwi]

Well, your picture answers the question itself. Your CPU should be constantly capped at 100%
You are low in RAM and Windows startend paging. Paging is mor than a 1000x slower and thus the CPU sits idle while waiting for new instructions.

Corona does currently not support out of core rendering, even if it would you would experience near the same performance hit. The performance hit will get worse the bigger your scene and will completely dissappead, once your Scend fits into ram.

Short tricks, in case you are on the edge of ram usage:
Purge Undo queue in 3dsmax,
Close all the porn tabs,
Don't use displacements for now,
Try whole scene with gray material override.

For more detailed help refer to the Corona helpdesk article on low ram. https://coronarenderer.freshdesk.com/support/solutions/articles/5000675854-system-is-running-low-on-ram-you-may-experience-excessive-parsing-times-and-or-crashes-you-will-pro

Or simply get more ram.

[Nekrobul]

Nope,

Actualy thehere wrere no such problem in 1.3 with memory overload.

Memory overload should only affect persing+ACC building time in some cases also processor heatup till 100% NOT the total usage of processor. Atleast it was in 1.3.

I did already ALOT of tests and i am still looking for temporary workaround or for at least what causes it.

PS - i will find solution, and if you belive in what you written here t will be your desicion not to use it )

[draxdamax]

Hi,

Of course, I will get more ram BUT I find strange (and frustrating) the fact that I am not able to rerender scenes I renderer normally with the previous version (1.2 or 1.3 can't remember now).
And this led me to believe there might be some kind of glitch (bug maybe) in the 1.4.

This happens also with the material override.

And the funniest moment was when I had the same problem with an older scene on a dual xeon with 96gb ram ...The scene I rendered with an older version on a laptop with 8gb.....
In that case I traced the problem to an converted proxy or material (from vray) but still something changed and might be broken.

I understand the slowness in parsing and building acc. phases but once the rendering is starting I think it should keep the cpu to 100% constantly.

[Ondra]

Memory problems - we have multiple reports on this, we are trying to find out what is causing this

[Juraj]

Close all the porn tabs,

I don't think such extreme sacrifices are necessary, but I can see, Chrome....

I also experience some "leak?" where a scene during precomputation reached far higher than it would take afterwards (40 vs 20 gb). I solved by 64gb upgrade on every node.

[Ondra]

that is just peak, leak would be memory that is never freed. Embree needs some extra memory for precomputation, same with displacement, 3dsmax, .... but 20 GB is extreme.

[Juraj]

that is just peak, leak would be memory that is never freed. Embree needs some extra memory for precomputation, same with displacement, 3dsmax, .... but 20 GB is extreme.

It only happened when going hi-res above 5-8k for very complex scene.