Performance issues

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Re: Performance issues

Post by Dez! » Fri Jun 11, 2021 5:28 am

Every morning I read 1-2 chapters from the Bible.
Look at the place I came across today:

Galatians 5-15:
But if you gnaw and devour one another, watch out that you are not consumed by one another.

About the road map and user surveys.
I used C4D for years and left for Blender because C4D developers don't listen to users and develop the product against the results of user surveys.
Blender developers listen to users and that's a success for everyone. This is the root of the community's fanatical love of Blender - everyone feels a part of it.

I can't program and I can't improve Luxcore code.
But I can visualize. I can contribute with the most precious thing everyone has: time. I'm willing to invest my time in Luxcore. And I'm already doing it. If you watch my videos above you will understand how much time I invest in each project. And every one of them I bring to a level where it promotes Luxcore and shows its strengths. It's the result of a lot of love. It's the result of a wide open heart.
I ask "how much does it cost to fix the viewport problem" is also a question of love, because I am willing to spend all my piggy bank to improve my computer to solve this problem.
I put other rendering engines and look at how they have implemented this function, how it works, redoing scenes to compare, I record clips, write reports, make comparative renderings - all this takes a huge amount of time. It's all out of love for Luxcore.
I'm helping to develop the 3SCloud render farm in relation to Lux, try it there, it works flawlessly! The developers and I have done miles of test renders, file downloads, and other research. And it all took an incredible amount of time.
All the Russian-speaking community with a question about Luxcore comes to me first. Not here on the forum. Not on discord. To me, in private messages on social media. Lots of downloaded scenes, test renders, and just writing posts explaining how and what works - all that time. All through love.

I'm incredibly invested in Lux!
If I spend time with love in my heart, I want to be heard, I expect a reciprocal investment of time.
If that contact doesn't happen, if there is no filling in the open heart, but there is silence - the heart closes and the love fades away.

This is what is happening to me now. When I hear "dude, relax," "your opinion doesn't matter.

My love fades when I see that my time is not needed or important to Dade, to Byob, or to the Luxcore community.

But my love is infused from Jesus, and so I keep hoping it will overcome that obstacle.

And I say it again: bevel-node, viewport, cryptomate. These are the keys to thousands of new hearts and Luxcore fans. These are the keys to the weight of the words "visualized in Luxcore. These are the foundations on which subject visualizers will be able to stand. That will fully reveal all the benefits of all Luxcore technologies.
These are the people who will reveal all the charms of caustics. Not the interior visualizers. But visualizers of cosmetics, perfumes, jewelry. These three technologies are important for all of them. The main one is adjusting the light and position of objects in the frame during the preview rendering in the view window.

I ask to be heard.
I don't want to look for a replacement in the plastic and dumb Corona.
I don't want to crash into the clunky Indigo interface.
I don't want to spend a huge amount of money on Thea.

It's all the rendering engines that are catching up with Luxcore. They're all a step or two behind. Right now. I don't want to take a step back. I want a step forward. Together with Lux. And ready to pay with time.
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Re: Performance issues

Post by Sharlybg » Fri Jun 11, 2021 9:14 am

There is basically a lot of stuff to be done. Lot of key feature ask about each time. And clearlly a single man can't handle all that pressure.
This is the reason why i propose the fusion or try to attract other sttruggling project. I'm not myself a Devs even if i want that. i don't know the
gap between addon/UI development and core engine development. It look like a huge gap as people in this field are rare and employed by big name :
Maxwell / Corona / Vray / Thea / keyshot / blenderfoundation ... While the others are sharp Einstein brothers doing E.T physics on computer ( Wenzel jacob & Co )
No matter what we say it will feel like adding more pound on our single core Dev. He even haven't to defend himself as the list of work he does for the project is so long. Even in his commenting stats he is miles away of everyone being the most active person on the forum.

I don't think Bigger community a more funding is his daily nightmare :roll: . But he isn't superman. A great guy but not a god. how can someone do the job of the entire render team of big money Blender fondation at his spare time and be there for all required feature. This mission impossible the list of improvement is huge :

Long time requested features

__ Smarter / faster Viewport
__ Artists friendly SSS
__ bevel shader
__ adaptive displacement
__ faster Volumetric rendering for smoke & co
__ Multiscattering rough glass shader
__ cryptomatte
__ hair shader
__ Separate clamping value for direct and indirect light

Performance related request

__ faster less noisier path tracer (fast enough to attract user from competition )
__ online learning algo
__ faster bidirectional engine

Quality features

__ SDS without cache and animation ready
__ efficient Spectral rendering

How he can do it alone while working on transfering all the current code in a single one for easier futur development ?
how he can do that while fixing bugs in the meantime ?
how he can do that while implementing quick features like adaptive texture to save memory or OCIO support ?

the bottleneck is there it is a one man Band it is extremelly risky. We do need to think about solving that. In the meantime add a bit of clarity and organisation.
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Re: Performance issues

Post by B.Y.O.B. » Fri Jun 11, 2021 10:19 am


I haven't read all the recent posts in this thread, but I want to say that I am aware of the viewport performance problems in complex scenes, and I think we should make it a priority to solve them. We developers should talk about the technical side of things in a separate thread (maybe in private, to tune out noise).

What you as users can do to help us is providing example scenes that show the problems, if possible with a short screencapture video showing it, and information about the hardware it was recorded on. Then we as developers can try to replicate the issues and investigate how to solve them best.

In general, I think that the UI of a program should follow two main principles:
- Even when doing the heaviest, longest computations, the UI should never hang completely. Long-running operations should happen in separate threads
- It must always be possible to cancel long computations. For example, if the user starts a viewport render in a complex scene, and the startup takes 30 seconds, it must always be possible to cancel the viewport render immediately during those 30 seconds.

Unfortunately, there are currently many possible situations in BlendLuxCore where these principles are violated.

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Re: Performance issues

Post by Dez! » Fri Jun 11, 2021 10:53 am

Blend: ... p=drivesdk
PC: Ryzen 5, 32 ГБ, SSD M2, Radeon GT 590 RX
From about 3 min. 30 sec. onward, it's hard to adjust the light source.
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Re: Performance issues

Post by Martini » Sat Jun 12, 2021 5:56 am

Thanks B.Y.O.B.

Viewport performance in order from worst to best:

* GPU with Light Tracing - almost hangs Blender in between each scene edit
* GPU without Light Tracing
* CPU with Light Tracing
* CPU without Light Tracing - pretty responsive, feels realtime

Sample video:

I was able to reproduce this issue simply by starting Blender, switch render engine to LuxCore, and set appropriate Viewport device settings. Of course, with heavier scenes, the performance gets worse, as the amount of data it needs to synchronise to the GPUs increases.

Tested on Blender 2.93 with LuxCore 2.6 daily, Windows 10 i9 9900K and 2 RTX 2080 Tis.
i9 9900K @ 5000MHz | 2x Gigabyte AORUS RTX 2080 Ti Extreme Waterforce WB 11G @ 2010MHz
Z390 Aorus Pro | 32GB Kingston HyperX Predator RGB @ 4300MHz

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Re: Performance issues

Post by Dez! » Sat Jun 12, 2021 6:31 pm

Martini wrote:
Sat Jun 12, 2021 5:56 am
Of course, with heavier scenes, the performance gets worse, as the amount of data it needs to synchronise to the GPUs increases.
Yes, so 5 years ago when the device switch for the viewport was removed, I insisted on bringing it back. And Byob was kind and gave it back. Thanks.

Martini, your testing shows that even extremely powerful equipment on a primitive stage has problems.

Can you do an extra test for me?
You have two video cards. One connected to the monitor, the other only for rendering? Can you use the Luxcore viewport video card for rendering?
If both the processor and the video card for the monitor are not involved in the viewport graphics calculation, what results would such a test show?
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