I managed to get both the image and the color profile from your test video.
For anyone else who wish to test with same image and profile, you can get the same image here and the color profile from here
My system configuration is :
- Operating System: Arch Linux
- KDE Plasma Version: 5.19.4
- KDE Frameworks Version: 5.72.0
- Qt Version: 5.15.0
- Kernel Version: 5.7.10-zen1-1-zen
- OS Type: 64-bit
- Processors: 8 × Intel® Core™ i7-4790K CPU @ 4.00GHz
- Memory: 31.3 GiB of RAM
- Graphics Processor: GeForce GTX 750 Ti/PCIe/SSE2
As you can see my system is old and has half of the ram that you have and I only assign 50% of ram like you so it means my result is from 16gb ram assigned to Krita.
Here are my test results with same steps that you perform: (all the time are approximated)
- Changing color profile to CMYK - 7 seconds
- Toggle channels - 5 seconds
- The slope offset, power and burn dialog - 5 seconds (s,o,p) burn preview - 4 seconds
- Different color profile resulted in different operation time.
I again tested this with another color profile - US web coated swop and got similar results
And then I did the steps with RGB, this was much much faster literally in 2-4 s for everything
From this test I believe that :
- Something is hindering Krita in your system as despite having approx half of your system config, my processes are completed nearly twice as fast as you.
- Working in CMYK is slow, it is one of the reason I don’t recommend working in CMYK from the start. I had written why here. This may be due to the fact that Krita needs to convert CMYK to RGB while doing operations and showing you the preview and image while working on screen (I am not a dev so don’t know the technicalities here my assumptions may be wrong)
I would suggest:
- Try the steps with RGB profiles and compare it.
- Work in RGB and at the last moment convert it to CMYK.
- If possible try these steps with same image and profile in someone else’s computer with different specs
Again I don’t mean to be defensive in this regard and put the blame of the slow process on your system config. CMYK conversion and other operations might need some love and optimization. We can request the developers here about this and provide sample files to solve this issue if it is possible. The suggestions I gave can be counted as workarounds until then.
To give you my personal experience while working with big files (literally 12ft x 9 ft 22,200px x 16,200px), yes the operation was slow but I have not experienced that much of slowness to the point where I bashed my mouse or keyboard. I was able to get my work done. I worked in RGB profile while checking colors with soft-proofing. I converted the image as a last step when sending to printer.
P.S. I have recorded the video of this test if anybody needs to see it they can download it:
On another note:
I read somewhere that xeon cpu are good for server type work and don’t really provide better results with image editing etc. This can be wrong and the difference might not even be noticeable. So take this point with a grain of salt.