Hey folks, we're using the feather procedural and the preview procedurals node in Solaris to render some feathers, and it's been working really well until now.

Since this morning I've been getting this OpenCL error:

Error: OpenCL Exception:
clBuildProgram (-9999)

Nothing changed since yesterday and the OpenCL error just spontaneously appears preventing me from doing any work locally, it still works on the farm.

Our graphics cards are Nvidia A10 with 24GB of video memory.

Is there a place in Houdini I need to increase a GPU Memory Limit or the like?

We've tried removing the Houdini Preferences and My user preferences and ultimately we tried creating a new Home directory (we work on Rocky Linux 8) and we also tried assigning me a fresh machine with the same specs to see if it was any corrupted caches or broken hardware, but none of it worked reliably. The error keeps returning.

None of the geometry or HIP setup changed since yesterday, and it's been working until today.

Any suggestions are welcome.

That's quite strange. Maybe double check whether drivers or anythinng about the OS was updated?

Can you try using the OpenCL CPU Driver? Under Preferences->Misc set OpenCL Device Type to CPU.

Is this with 20.0 or 20.5?

If on 20.5 I could also imagine the OpenCL cache being corrupted, not that I've seen or heard of that happening. It just comes to mind because of this sudden failure. Maybe you ran out of disk space temporarily which caused a corruption?

You could try deleting the contents of $HOUDINI_TEMP_DIR/OCL_CodeCache

or alternatively try setting the environment variable HOUDINI_OCL_CACHE_ENABLE to 0 (although you probably want to reenable that later on)

Make sure you try a current build as well, I know for a while there was a bug in the 20.0 procedural which only occured with certain segment counts. Maybe you changed that at some point recently?

Hey Kai

Thank you so much for the quick replies. Switching to the OpenCL CPU driver did the trick. It's not as fast, but at least It works every time.

We tried updating to the latest Nvidia Drivers and that didn't solve the issue. But it's weird that it seems to be sporadic.

Some days there's no problems, then the next day, without any changes, the same scene will not render.

Hopefully H20.5 will have many of these issues solved when we switch after this project.

Thank you again for the replies!

I had the same issue in 20.5.332 and deleting the contents of $HOUDINI_TEMP_DIR/OCL_CodeCache did the trick, so thanks!