Is 1.6 slower than 1.5 ?

[Grisha_J]

Hello guys,
Spent a few hours testing a new 1.6 and noticed that the new version is a few percents slower than 1.5.
Render time in 1.5 was 33 min (100 passes), but render time of the same scene in 1.6 was surprisingly higher - 39 min (100 passes)!
The interior scene contains corona scene environment (solid color) plus corona sun - no hdri.
Thank you.

[bluebox]

And have you compared the noise level after those 100 passes in both cases ?

[Ryuu]

Hi, there have feen few changes which might lower the brute force performance (meaning more time per single pass) but should overall cause the image to clean up faster. So you should need fewer passes to achieve the same quality.

Could you perhaps try rendering with a set target noise level instead of pass count to see if that's still slower?

[Grisha_J]

The noise level is an issue as well.
In 1.5 was 3.0, in 1.6 was 3.13 - visually the picture in 1.6 was slightly noisier in comparison to 1.5.
Additionally I forgot to mention in my last message - the 3d scene contains a few equal ies lights in order to illuminate the room.

[Ryuu]

Could you please send us the scene for testing? If you don't want to share the scene publicly, you can use the private uploader from my signature.

[Grisha_J]

Alright guys - it's done:
Successfully uploaded as 1493410662_CoronaTest.rar
I uploaded a different scene - but the situation is absolutely the same.
My home i7 6700k does it in:
V1.5 - 52 min.
V1.6 - 59 min.
The noise level is approximately the same, but the render time difference is more than 12%!
I look forward to hearing from you guys.
Thank you.

[cecofuli]

From my test, 1.6 is slower, but not so much.
In the link, you can download the SCENE and the CESSENTIAL Render Elements.
For the same amount of time (15 minutes) I have:


1.5.2
Rays/s= 1.938.000
noise level= 5.7
Passes= 72

1.6
Rays/s= 1.820.000
noise level= 5.99
Passes= 67

--- DOWNLOAD ---

[Grisha_J]

Thank you for input Francesco - let's wait developer's response.

[Grisha_J]

Is there any progress with my question and 3d scene? Will the speed issue be fixed in the future?

[Ryuu]

Thanks for the scene and for the measurement. I haven't had yet the time to compare the performance myself unfortunately. We have multiple optimizations scheduled for 1.7 so this will definitely be addressed.

[jjaz82]

i noticed same issue, a little slow, same passes but a little bit noisy.

[Flavius]

Yes, clearly 1.6 is more noisier,  I haven't tested it properly (busy) but it feels noisier, also in the IR which also seems to be a bit less responsive compared to 1.5.

[Grisha_J]

Yes, clearly 1.6 is more noisier,  I haven't tested it properly (busy) but it feels noisier, also in the IR which also seems to be a bit less responsive compared to 1.5.

I agree - IR in 1.5 is more responsive and comfortable.

[Ondra]

that is weird, as it goes directly against experience of other users. What is your system specs? Does it happen in all scenes?

[DarcTheo]

Yes, clearly 1.6 is more noisier,  I haven't tested it properly (busy) but it feels noisier, also in the IR which also seems to be a bit less responsive compared to 1.5.

I agree - IR in 1.5 is more responsive and comfortable.

1.6 IR is amazing for me, I can do so much more now. in 1.5 it was very hard to use IR sometimes but in 1.6 it is a lot easier to not crash the PC while working with it.

[Grisha_J]

DarcTheo - If you are talking about crashing, as for me 1.5 has pretty much the same stability as 1.6. Flavius and I mentioned the IR responsive of 1.6  which is different (especially first few seconds after starting) compared to 1.5.But this is secondary.
The most serious issue is the speed, which in my understanding should be increased after each major update, or at least should stay the same.

Ondra - the speed issue happens in all scenes.
Configuration: i7 6700k ; 1050Ti; 16gb ram.

[cecofuli]

are the differences very "important"?
In my test, in 15 minutes, the difference is between Noise Level 5.7 and 6.0 = 0.3
In my opinion isn't so big. Anyway, van you share to us more info and, maybe, both rendering 1.5 vs 1.6?

Thanks

[Grisha_J]

I am sorry Francesco, but I don't have rights to share this scene.But developers of course have this scene and can test it - I uploaded it 2 weeks ago.
Based on my tests, this particular scene shows a difference as I wrote before - 12%!. In my opinion 12% is serious - I would say huge difference.
Also - I've described the negative sign of the new version. I don't think for most of us decreasing of performance is "not a big deal".I thought we spend  periodically our money, and update our cpus exactly for the performance.
Again I'm not complaining - I'm just trying to help and improve this great product.

[cecofuli]

Yes, 12% is too much. but, I think that, if there is a problem, the Corona Team will solve it.
Maybe your scene is a "special" scene.
I think that the Corona programmers did a lot of test  before 1.6 release, to know the 1.6 average performance =)

[Ryuu]

Some of our users found out that we have an unfortunate performance problem with VFB refreshing. The refreshing of the VFB contents (+ applying all the tone mapping operators) just takes too much of the CPU time.

We have identified the issue in the code and it will definitely be fixed. We'll discuss this internaly but from my point of view the code changes needed are so extensive that I wouldn't want to risk doing this in hotfix and so it will be fixed in 1.7 (daily builds).

In the meantime as a workaround you can try:

• Disabling sharpening during the rendering
• Zooming in the VFB all the way in
• Closing VFB during the rendering

I think that just the first step (disabling sharpening) should give you the biggest performance boost while still being only a minor inconvenience.

From the initial reports just zooming in to 1:32 can speed up rendering by up to 10%.

[cecofuli]

That's great =) I'm sure you will solve this "bug" soon

[Grisha_J]

Thank you Ryuu - we will wait new update!

[lupaz]

Was this fix on any hotfix?
Did anyone go back to 1.5? Is it possible to go back from 1.6?
Thanks.

[maru]

Was this fix on any hotfix?
Did anyone go back to 1.5? Is it possible to go back from 1.6?

Which fix do you mean specifically?
You can go back even to 1.0: https://corona-renderer.com/download/old

[lupaz]

Got it.
Thanks.

In the office they're using 1.6 hotfix 3.
With a heavy scene, the subsampling was very annoying, because it was erasing the vfb with every move. I lowered the subsampling to 1 and it's the sweet spot.