Only recently I made the switch to DT v4 and while I love the new version, there is a problem with generating thumbnails of large Tiff files.
Setup: Linux Mint 21, DT 4.0.1, 16GB Ram.
A folder with 7 TIFF images 16-bit CIELAB of 900MB each is opened and thumbs are being generated. All at once.
RAM gets filled up completely by DT first, then the swap file until everything is eaten up and Darktable just vanishes.
It happens with OpenCL on and off.
I cannot prevent the parallel computing of 7 thumbs by lowering the worker_threads number in the darktablerc config file.
The generate-darktable-thumbnails tool seems to quit silently after some time for the same reasons.
Any idea how to prevent the crash or restrict the overall numbers of previews that are being generated simultaneously?
Ouch!
I’ve no idea what to do about it, but on my low end Win 10 laptop with only 4gb ram dt sometimes crashes for a similar reason in the lighttable view. It gives a error though, and a backtrace. I think it’s ok if I’m not running anything else at the same time. My desktop with 16gb is fine.
Good luck
You can limit the size of thumbs but still 900 MB is just the stored size…then to open such a file requires a lot of ram… try a directory with just one and turn on the performance modules and see where that leaves you… Then you can try to tweak some settings but working with files of nearly a gig on a 16gb ram machine seems to be asking a lot…maybe I am not clear on the details…
Thanks for the feedback so far. I would like to elaborate my problem with more details:
I know that DT works in 32-bit floating point. To read a 1GB 16-bit Integer CIELAB TIFF into 32-bit FP will require double the RAM and triple the RAM if we take the output buffer into account. Still, 3GB would be sufficient if DT would not try to work on 7 thumbnails at the same time. Limited to four should fit into the RAM.
I thought DT would begin to tile images when RAM is not sufficient. Is thumbnail creation excluded from this behaviour?
Don’t understand me wrong: if there is no way of tweaking the behaviour, I will bite the bullet and upgrade the RAM. However, it would be sad to use it solely for thumbnail generation and then it would sit around empty all the time.
