Did Iray get slower in recent versions of Daz?
tl155180
Posts: 994
Hello. Serious question:- Did Iray get slower in recent versions of the Daz3D software?
I've been using version 4.9 for the longest time now, because I had everything set up the way I liked it and didn't want to mess with anything, but recently I had to get a new SSD drive and decided that now was the time to take the plunge and upgrade to the latest version. So now I'm on version 4.12, but the scenes in my library that used to render in about 20 mins on my old 4.9 setup are taking much, much longer than that now (well over an hour). Any theories on why that might be?
I have a couple of theories that someone might be able to expand upon for me:
1) I used to use almost exclusively emissive flat square planes for my lighting (with the occasional spotlight to add specular shine), because it rendered very quickly and I liked the fill effect and softness of the lighting. Perhaps the latest iteration of Iray is a lot slower to render light from emissive planes now?
2) My old render settings got lost in transit, so all the old settings I had in categories like Progressive Rendering and Filtering that sped up renders and removed a lot of the noise quickly have all defaulted back to normal - and I can't for the life of me remember what they were set at. Does anyone have any suggestions here please? I remember having very different settings for max & min samples and max time, for example.
Any help would be appreciated, as I'm sure it can't be that Iray just got a lot slower. Thank you!
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Do you have an Nvidia GPU with up to date drivers? Because my first guess when reading your post would be that scenes which used to be rendered with the GPU are now rendered with the CPU.
If you follow along with the Iray benchmarks thread, they're always testing new versions of Iray and new drivers and comparing to older ones to keep track of performance. Apparently Iray rendering has become slower in recent drivers.
4.12 requires pretty recent drivers, otherwise it wouldn't even run. I've done numerous tests lately and when I rolled back to driver 436, the newer 4.12.1.109 would not render at all. I can't remember if it crashed or not.
I have experienced slower renders in 4.12.1.109, and I think they are due to drivers. It just so happens that 4.12.1.109 with its updated Iray needs these drivers to function. However I still have previous versions of Daz installed. I have a version of 4.11, and several versions of 4.12, with some before the RTX update and after. When using the latest drivers, all of the version of Daz Studio I have are slower, even 4.11. If I roll back drivers to 436, then I can get that speed back, at least in all the versions of Studio that 436 can run. I have tried numerous other drivers, I believe every different driver that 4.12.1.109 can use, and none get the speed that driver 436 had.
So that tells me that this is a driver problem. I am not alone, as you can look at the last 2 pages of this benchmark thread and see that nearly all the recent posts have been slower than the previous versions of Daz Studio before 4.12.1.109. The only exception being the user with two 2080tis. But all the other users have seen big drops in performance with 4.12.1.109 and its Iray.
https://www.daz3d.com/forums/discussion/341041/daz-studio-iray-rendering-hardware-benchmarking/p1
The benches on the last two pages have not been posted on the big list that's on the first page. If you look at them, you see some people are anywhere from 30 seconds to a minute or more slower than other tests that predate 4.12.1.109. And when you have a benchmark that only takes a few minutes to run, that is a big difference. I also noted in a few posts these comparisons.
Its funny you should say that because it does feel like CPU rendering speed. My GPU drivers are up-to-date though because I just reinstalled Windows 10 and all drivers etc.
Does everyone have both CPU and GPU ticked for use in the hardware tab, or do you just use the GPU?
Hmmm.. so sounds like it did just get slower then. Thats unfortunate. I really regret updating Daz Studio now :(
What about the "Progressive Rendering" settings? Any suggestions there please? I can't remember what I need to have min and max samples set to.... but I know that I never used the default settings.
There is no such thing as what settings "need to be". Its all subjective, you could ask a dozen people and get a dozen different answers. All the max settings do is tell Iray when to stop rendering. So if you wish to render longer for a possibly clearer picture, increase them. You can always stop the render yourself when you think it looks done enough. Out of convergence, time, and sample count, the render will stop for whichever one is reached first. So even if you increase max time, it can stop on the sample count or convergence long before that is reached.
Thus you want all of these increased if you wish most renders to go longer. Render Quality is not a stop condition, increasing it can increase clarity, but will greatly increase render times. Just going to 1.2 can double your render times, assuming the stop conditions allow for it.
I've rendered the same scene in 4.10 released, and the current 4.12 beta, and it takes almost twice as long to render in 4.12 as 4.10. My GPU is a 980ti, latest driver release. My thinking is it has something to do with the change in OptiX Accelleration between those Studio/Iray versions, I believe 4.12's Iray implementation is focused on the newer RTX cards, which may be a reason for the decreased performance in my case.
As a result I'm staying on 4.10 until I get a newer RTX (or whatever comes next) GPU.
@tl155180, It was also explained in one of the beta threads, (by Richard Haseltine, if memory serves,) that the files for Iray are now several times larger than they used to be because Iray does a lot more things than it used to. (I'm probably not saying that quite right, as I'm trying to remember what was said.) The short of it is, each iteration/sample of Iray rendering takes longer than before, but you should need far fewer iterations/samples to reach the same quality.
Believe it or not, it may help to set Quality Enabled to off.
There are three "stop conditions" the rendering algorithm looks for to determine the end of the render. One of those is the Convergence Ratio, which gets disabled when Quality isn't used. The other two are Max Time and Max Samples.
You can then control when the render stops by either setting the length of time in Max Time, with Max Samples set to a very high number, or the other way around. However, you can actually disable Max Time with a 0, (zero,) in the parameter and then control the length of the render completely with the Max Samples setting; Low values for test renders, and high values for final renders.
Are you using the drivers Windows provided, or did you go to NVidia after reinstalling Windows?
Thank you to everyone for your suggestions and explanations. Its much appreciated.
I always install my GPU drivers direct from NVidia.
It seems to me the recent drivers have become measurably slower, but not really noticably so. Nowhere near CPU slow.
Massive impact, depending on your taste in renders, is the post denoiser filter. Like 10x faster if you don't mind a "photoshopped" look. Must be set to both "available" and "enabled" (no idea why).
Spectral rendering and caustics are really expensive.
And of course, exceeding GPU Ram with shiny new textures and falling back to CPU. Check your task manager.
I exclusively use photoreal mode now, progressive has too many drawbacks for me.
For the denoiser, the first option makes it available. You can actually turn the denoiser on and off while the render is still running, which is where the 2nd option to enable it turns it on. There is a tiny triangle you can click to pop out a menu during an active render. In this menu you have several post processing effects you can try, all while the render is running. Do note some of these options restart the render from scratch.
I'm not feeling that explanation, because that would be down to Iray itself, not the drivers. For one, I can boot up Daz 4.11 with the new driver 446 and my renders are slower than driver 436 in 4.11. This version of Iray has no RTX or other features. The driver by itself should not going to alter how Iray functions.
But another super easy way to test the idea that more work is being done per iteration is to simply look at saved images of the same scene rendered by different versions. The benchmark scene linked is a good test for this because it runs exactly 600 iterations and stops. When I run the bench with 4.11 or 4.12, it doesn't matter, they look pretty much identical to each other. If Iray was actually doing more work per iteration, then I would expect that the new 4.12 to look more converged than the other versions. Since it doesn't, that also rules this argument out.
I also have numerous scenes that I have saved before in 4.11 or early 4.12, and they all take longer now to reach the same level of "done" than they used to.
So my conclusion is this issue is not Iray itself. It is not any CPU security patch effecting performance. It is the driver.
The CPU renders have gotten faster it seems on my PC.
When I first downloaded the upgrade, I started crashing on anything more than a single character with hair. I was starting to get a little discouraged. Then I clicked on the Render Settings Tab / Advanced, and clicked the CPU option. My renders are lightning fast now.
yes I believe your right about the drivers does havr a lot to do with render times. That is why I never moved from daz 4.12.0.35 which can use the NIVIDA driver 436.30, any newer versions of Daz or GPU drivers throws my 1080ti's to cpu
I render in Blender; my CPU is quicker than my 980ti. In studio, the 980ti is about 40% faster. Of course, time taken transfering to Blender takes time, but I prefer that than "waiting for a render". You don't have to use Iray, there is Octane available as a free plugin for Studio, and 3Delight.