Hello,
I hope you can help me with the following problem.
With the newest driver versions (555.99 and 560.70) we have the problem that our program randomly freezes during the update of the acceleration structure, so that we have to kill it in the task manager. I cannot provide our code here, but I noticed that at least the demo program optixSimpleMotionBlur also freezes after a few seconds.
The problem happens on most of our test PCs where it seems to be crucial that hardware-accelerated GPU scheduling is disabled in the windows settings.
For the test program I used optix 8.0.0 and cuda 12.5.1, but in our program we also have this problem with optix 7.6.0 and cuda 12.4.1. We compile with Visual Studio 17.8.11.
One of the systems that produce the freeze has the following properties:
Intel(R) Core™ i9-10900X CPU @ 3.70GHz
NVIDIA GeForce RTX 3090
64GB RAM
Windows 10 Enterprise (22H2)
Besides these freezes, we also get this warning in our unit tests with the new drivers:
[MEMORY]: cblCmdListBufferSize insufficient, attempting allocation
It’s hard to find any information regarding this warning or cblCmdListBufferSize at all.
Yes, unfortunately that is a known issue which is fixed inside the next R560 driver release.
The only known workaround for end customers would be to enable hardware scheduling or revert to R550 drivers.
It’s related to the new launch mechanism inside R555 and newer drivers.
For development, there also exists an environment variable OPTIX_FORCE_DEPRECATED_LAUNCHER which affects which launcher is used.
That can be set to CBL1 or 1 to switch away from the default launch mechanism.
Please only use that environment variable during development, not in any shipping application!
I’m really sorry about that.
Checking the history for the driver branch from which 560.81 was released, shows that is was cut before the fix.
Means this needs another R560 driver release which should happen this month.