How to avoid long parsing time?

[Bormax]

Hi

Mostly working with exterior scenes I have situations when files with about the same amount of objects, tree models, cars, etc., have quite different parsing time. And this difference not about few percent, for example one scene has Scene parsing time 9 sec, another one has 1min 20sec of parsing time. As I said they are about the same - trees, grass, cars... Was thinking, that problem is some object in scene, but excluding groups of objects from rendering (trees, then grass, then cars and so on) I made parsing time go down proportionally in both scenes, so I didn't find any particular object/s which can affect to parsing time so much.

So I'd like to know:
What the Scene parsing process is?
What determines the time for parsing?
How to avoid long parsing time?
And would be interesting to hear your ideas what can be wrong with the scene described above? You can find attached screenshot with this scene, parsing time here 1min 10sec - 1min 30sec

Thanks in advance!

[maru]

Are you using some 3rd party plugins in this scene? Can you think of any differences between the scenes where parsing is fast (e.g. few seconds) and slow (e.g. one minute)?

I am also concerned about the "0" stats in your VFB... looks like something is wrong here.

[Bormax]

In both scenes Forest pack used for grass and background trees scattering. As I said excluding those object from rendering reduce parsing time proportionally, it means if grass is not renderable, parsing time about 20% less in both scenes, the same with trees. Buildings in both cases are adopted archicad models, parsing time for rendering only them takes in both cases 1 second.
Experimenting today with slow scene I've got this statistic for rendering parts of the scene separately:
Building with forest - parsing time 2 sec
Building with trees on foreground and bushes - 4 sec
Building with cars - 2 sec
Building with grass - 11 sec
And - SURPRISE!! - after these tests I rendered again everything and got only 20 sec of parsing time. Saved this file with another name, opened old file again, and got 1min 50sec  when I rendered 1st time (as before when it was 1st render after opening), and next renders take now 20 sec for scene parsing... Do not have any idea what can be the reason for this. Last time I did tests 22.01, when I asked about CPU usage in daily section, then I got stable 1min 10sec of parsing time for whole scene (not 1st rendering), the same was before, when I was working with this scene - that was the reason to ask about it.

[Ondra]

this sounds like some cached precomputation on the side of forest pack - probably nothing we can do about it. You could send us the scene so we could confirm it

[Bormax]

Hi

It looks like I found the problem point. Quite often I have simple animation for the sun for different cameras, and I've noticed that if I don't change frame number I get few second of parsing, if I change frame, parsing time grows. Finally I found that the problem is in proxies, actually in Enable animation of them. Even if the proxy was created as not animated, this checkbox has influence on parsing time.

Example file uploaded with private uploader 1486622037_box-proxy.zip

Simple scene with only one proxy - box, subdivided to rise polycount. Open it and start render - parsing time is 0, change frame - parsing time 2 sec. Check Enable animation on, don't change frame - parsing time 0 sec, change frame - parsing time 2 sec again.
In big scenes it's also dramatically slows down feedback time of IR

I made the same tests with proxies of trees, there I've got difference like 2 sec - 21 sec (worst result). Probably more proxies in the scene - bigger difference of parsing time.
Is it a bug, or some problems on my side?

[romullus]

Sounds like a bug to me. Could you make new report in the bug reporting board or Mantis?

[Bormax]

Done

[iancamarillo]

was this fixed in 1.7 hotfix1?

[iancamarillo]

I haven't updated the machines to 1.7 hotfix1 but after I disabled animation on thousands of proxies, my parsing time for each frame dropped from 20min to 3min. Probably saving me days to complete. I'm still testing to confirm this though. I attached a script I made to disable animation from all selected proxies.

[3dboomerang]

guys is this comfirmed or not, i'm using animated proxies and i'm struggling with annoying parsing times. I'm also using forest pack

A follow up would be welcome?...

[iancamarillo]

this sounds like some cached precomputation on the side of forest pack - probably nothing we can do about it. You could send us the scene so we could confirm it

Hi Ondra, I've uploaded an archive to your dropbox. When I send you a message it doesn't show in my sent folder. Can you let me know if you've received the files and message? Thanks

[TomG]

Rather than message any individual, it's best to message support. The main thing about messaging an individual is that they may not be there when you message them, but there's always someone manning support. PS - Ondra isn't around just now :)

[iancamarillo]

Got it. I'll resend the message to support now. Thanks

[iancamarillo]

Hi Tom,
Is there a dropbox for files over 2.5gb that support has access to other than ondra? Also, what is supports PM name? Thanks

[TomG]

Yes, info is at the bottom of https://corona-renderer.com/upload

There's no generic forum account for support, you should email them at support@corona-renderer.com (as then things are in the tracking system and won't get lost - can't track forum PMs :) )