I have been using darktable for about 9 months and so far have had no real problems. I have just bought a 2nd camera (Lumix GX80) as a second to my Nikon d5600. On processing the first set of images (.rw2 files) and exporting the first image I got the message: “tiling failed for modulr demosaic output may be garbled”. The computer (2015 iMac 32Gb RAM, 2Gb GPU RAM) immediately started gobbling up memory and using 5-700% of the available 800% CPU. I was using darktable 4.2. I’ve tried selecting different demosaic algorithms and I’ve updated to 4.2.1 but the error is still there on all my images, i.e. older .NEFs as well as .RW2.
Can anyone give me any way to fix this? It has completely trashed all my work with darktable.
you might run darktable from terminal: darktabe -d opencl to check if the dedicated gpu or the intel on-cpu gpu is used for processing the full pixel pipe.
then you can try to manually control how the pipes are processed. with my old macbook pro the on-cpu gpu was preferred for full pixel pipe instead of the faster dedicated gpu.
you can do this by tweaking ~/.config/darktablerc line:
e.g. opencl_device_priority=1,0,*/!1,0,*/1,0,*/1,0,*/*
in my config that forced the full pipe to be processed with dedicated GPU, preview with on-cpu-gpu, same as full for export and thumbnail pipe , and no preference for second preview window. But you need to find the best config for your system…
this just works if you select “default” in opencl oprions in preferences dialog.
maybe you also need to tweak the opencl resources and memory handling options in darktable preferences
Thanks for this. I was suspicious of opencl but given my limited amount of GPU RAM had not fiddled with it. You mention darktable preferences but I can’t see how to access them. There is no [Preferences] option on the menu.
As it happens I think I have found a work around that I am hoping will continue to work. Since it had worked for 9 months and, to the best of my belief I had made no change to my system, I wondered if perhaps something had been overwritten in the config that caused the problem. I deleted the .config directory and then started darktable again. After adding my library I loaded the image that seemd to have caused the problem and exported a JPG with no problems. I am hoping that is a continuing fix.