OpenCL hang on OS X
After activating opencl on os x (10.8.3) - on a retina macbook pro ( nvidia GT650M) - loading an image into darkroom (or adjusting one thats already opened), the application hangs on a spinning beachball and must be killed.
#2 Updated by Ulrich Pegelow about 6 years ago
There's not too much we can deduct from the available data. Obviously darktable hangs when waiting for OpenCL events to terminate. This is an indication that some OpenCL operation has crashed or got caught in an endless loop. There are a few things you could test:
1) set config parameter opencl_number_event_handles to -1. This will effectively prevent darktable from using the OpenCL event mechanism. Has a lot of drawbacks but might at least indicate if there is an issue on your OpenCL implementation just with that mechanism (not very likely).
2) set config parameter opencl_avoid_atomics to TRUE. We know that atomic operations is a difficult topic with some devices.
3) download some of the many OpenCL demo or test programs from the internet and check if your system has a general issue with OpenCL
Unfortunately none of the developers has the ability to test your specific setup (Macs come with their own OpenCL compiler which might or might not play well with a specific GPU). So If none of the above helps, the only option might be:
4) deactivate use of OpenCL in core options and run happily with CPU processing