So I still am still unsure of the BEST workflow....

[^Lele^]

I can SOOOO challenge that notion.

Sure. Head over to the beta group though, so not to confuse the rest of the users.
It's really been thoroughly tested and demonstrated, and i'd rather not restart a closed argument in public.
kosso_olli , read above, if it's more than around 10%, it's likely an issue, report it please.

[kosso_olli]

kosso_olli , read above, if it's more than around 10%, it's likely an issue, report it please.

Here is a test from a production scene. 4K resolution, one domelight and an area light in the scene, some VrScans, DOF. Bucket mode took 47 minutes, while progressive took 64 minutes, so progessive was around 36% slower. Noise threshold was set to 0.01. Noise pattern is different of course, but they look identical. One thing that I liked about progressive is a little highlight in the DOF, which came out much cleaner for progressive. However, a 36% render time hit is to much for us. I am sure it will get worse the higher the render resolution gets.

First is bucket, second is progressive.

[^Lele^]

It'd be great if you could save a scene with either render setting, and send it over to support for profiling.
I can imagine a bigger size render suffers more of the all-image noise level detection than a smaller one (that's also why you get a slightly better DoF than with bucketing), but that shouldn't be enough.
*Many* REs *do* slow down progressive compared to bucketed, but then we're talking 10-30 and more REs at once, is this the case?

[kosso_olli]

It'd be great if you could save a scene with either render setting, and send it over to support for profiling.
I can imagine a bigger size render suffers more of the all-image noise level detection than a smaller one (that's also why you get a slightly better DoF than with bucketing), but that shouldn't be enough.
*Many* REs *do* slow down progressive compared to bucketed, but then we're talking 10-30 and more REs at once, is this the case?

Yes, there are around 15 Renderelements in the scene. I will pack it up and send it to support.

[^Lele^]

Yes, there are around 15 Renderelements in the scene. I will pack it up and send it to support.

Super!
I've meanwhile written a script to measure the "slack" in progressive versus bucket, and output a CSV, with a few conditions (with and without tiled textures, or proxies, which need to unload; with and without many REs, at small and bigger image size, and so on), to help figure out possible bottlenecks.
I'll update it as i'll get your scene to better reflect a production setup case.

Would you be so kind to CC me in the mail to support?

[im.thatoneguy]

I can SOOOO challenge that notion.

Yeah, I've never found buckets to be slower. Almost always substantially faster. I didn't realize that was considered a bug.

[^Lele^]

Yeah, I've never found buckets to be slower. Almost always substantially faster. I didn't realize that was considered a bug.

There were two notions in my post, which were quoted.
One was progressive for which i said it should be within reasonable range.
I mentioned also aa few caveats: It can be made much slower than bucket if one wants, just make the resolution huge, and there you have it.
At 2k, 10% ought to be the norm for a plain image.
There are a number of other things at play with it, however, due to the nature of progressive, like tiled textures, proxies, and so on, which won't play that well with progressive algos in general (not even with the LC, to an extent), as mentioned in the RAM saving guide.
There is however no difference in convergence rates between the two algos, which is really what i meant to say: the difference is due to ancillary issues, not intrinsic ones (like for other engines.).
The other point made was fiddling with local subdivisions while keeping a low amount of AA, which i prefer to take to the beta group if needs be discussed.
I am not sure which notion was challenged there.

[kosso_olli]

Would you be so kind to CC me in the mail to support?

Yeah, sure. I didn't send anything yet, will do that tomorrow. Promise.

[^Lele^]

Yeah, sure. I didn't send anything yet, will do that tomorrow. Promise.

No rush on my part.
Am currently brawling hard with Max and the creation of many lights: a fight that will take me a bit of time to lose. Win, i meant win. ^^

[kosso_olli]

You got mail!