Arnold "Number of vertices changed between motion steps" errors

[jinseok]

Hi, everyone.
I have an issue with the motion blur in arnold render with error “Number of vertices changed between motion steps” in Deadline.
I have this messege in houdini console but it render normaly in local machine, but Deadline might still detect the ERROR mesasge in the log, and stop the render.
Is there a way to tell Deadline to ignore errors?

[Justin_B]

It is possible to have Deadline ignore error messages by adding an additional standard output handler that’s attached to a function that doesn’t do anything before the generic error handler.

So in this case on line 47 of DeadlineRepository10/plugins/Arnold/Arnold.py you’d add this:

self.AddStdoutHandlerCallback( ".*Number of vertices changed between motion steps.*" ).HandleCallback += self.IgnoreStdoutError

Later on in the file you’ll need to add a function like this:

def IgnoreStdoutError(self):
    pass

Just be sure to make a backup copy of your Arnold.py file before making those changes, so you’re able to roll back.

[jinseok]

Thanks Justin.
I tried to modify Arnold.py. But has no change. Did I miss something?
Attatched screenshot.

[Justin_B]

In your screenshot it looks like the Arnold.py file hasn’t been saved yet. You’ll also need to re-submit the job so a cached copy of Arnold.py from the last job isn’t used.

[jinseok]

Hi, Justin. I’ve already saved Arnold.py and re-submitted jobs and new jobs as well with no success.

[zainali]

Hello

I have seen in the past, there may be Worker data still around with unchanged plugin. What you can do to test is to change a job setting from right menu options of the job> Modify Job properties> General> Reload Plugin Between Tasks and retry.

[jinseok]

thanks zainali.
But it doesn’t seem to work.

[jinseok]

and activated ‘Force Reload Plugin’ in Deadline scheduler in houdini.

[zainali]

Hello @jinseok

Can you attach the plugin file here from [Repo]/plugins/PDGDeadline/PDGDeadline.py

Or if you are using a custom plugin directory please share the plugin file (PDGDeadline.py) from there. I will change it for you so you can test.

[jinseok]

Thanks Zain.

Here is our python file for PDG from repository.

We don’t use custom plugin.

Thanks.
PDGDeadline.py (28.9 KB)

[jinseok]

Hi, Zain.
Any news for me?
Thanks

[Nreddy]

Hello @jinseok

I have added an standard output handler under the InitializeProcess function of file PDGDeadline.py that’s attached to a function that doesn’t do anything.

Please download the attached file, take back of your existing PDGDeadline.py file and replace with the attached file and see If that helps !

Thanks.
PDGDeadline(1).py (28.9 KB)

[jinseok]

Thanks Nreddy
Unfortunately. I don’t have any change.

[Ahmed_Hindy]

any update to this? having same issue over here with HtoA in Solaris

[jinseok]

Hi all, we tried to apply the patch suggested by the deadline team but the problem persists. I understand that the code tries to find for the error in the arnold stdout and bypass the error raising, so we tried that approach in a bunch of different positions in the code but to no avail. Please help as this is making farm rendering in Houdini with arnold unusable with variable vertex caches (like fluids).

[Ahmed_Hindy]

I found a bypass but I dont like it much. dont cache out your used sequences as usd, let the renderer read the SOP data live without caching it to disk as .usd

This may introduce problems with deformation motion blur but if you have different vertex count then you probably wont need it.