DT 2.4.0 taking a really long time to export jpgs.

I have never seen anything like that and am not aware of reports similar to yours.

  • What operating system are you using?
  • Could you please have a look on the terminal (or in the logs when on Windows) to see if darktable reports to have exported the image several times?

Just a wild guess: it might be that the configured tile size is too big, so instead of using tiling to keep everything in RAM the system starts swapping.

Ah - thanks; I have discovered that although I have assigned half my RAM (8 Gb of 16) in “host memory limit in MB for tiling” the "minimum amount of memory in MB for a single buffer in tiling takes precedence - at least, that is what the tool top says if it set to a positive non-zero number.

The trouble is, I cannot set this value to zero (or a negative value). Trying to overwrite it, or using the plus/minus buttons, I cannot get a lower value than 2. How to override this?

Maybe i just set it to a huge value - 1024MB?

No, no greater than 64MB allowed.
And no less than 2MB.


That is what I wild-guessed as well. Anyway, I don’t use dt much but out of curiosity I have a copy handy on my win7 system (4GB RAM). I tried the equalizer module on DSCF1719.RAF (PlayRaw) using a preset with normal bounded the only history item. Sure enough the fan whirls and the processing takes a long time to complete. My fan never turns on using other apps that we talk about on this forum. I just want to confirm that @Isaac isn’t the only one encountering this problem, though for reasons I mentioned in another thread, I won’t be able to investigate further any time soon.

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Thanks @afre for the confirmation! I will be examining a good processing tool chain in darktable for underpowered machines. I might write a short blog post about it if I get time…