Recommended maximum new image size for computer with 16 GB RAM? Beyond into swapfile?

[pstein]

I clicked on menu

File--->New

and try to create one with 3000x15000 pixels (see attached snapshot).
Much to my surprise I got a warning popup that gimp will create an image with size of 475 MB.
A simple image with pure white background?
I guess its the uncompressed size (not .png or *.jpg format)

And yes the maximum image size in Preferences is about 128MB

What would be the recommended maximum image size for a computer with 16GB RAM?

Whats would happened if I create an image beyond my maximum?
Will the new image be saved (completely) into (and handled from) swapfile on SSD/hard disk?
Or will it be rejected?

   

[Ofnuts]

Gimp work on uncompressed image, which is all the better, because compression uses CPU. And  you would be very surprised if your 200K image (because it(s all white)  blew up to 500MB just because you added some noise in it...

So yes, your image is 3400 * 15000 = 51Mpx so with 4 channels at one bye each, a single layer of the image is a bit above 200MB. So you have the 200MB background layer, a 200MB buffer where the whole image is rendered, and likely a 51MB selection mask, so it all adds up to a bit more that 450MB.  

After that it all depend on what you do with the image (undo steps are often copies of the modified layer...). The very important setting is the "tile cache size"(*) which is essentially how much RAM Gimp will use before overflowing data to disk (which it can do a more efficiently than the default system swapping) but can still slow it down considerably (but at least only Gimp is bogged down). I set it to whatever the system+usual apps don't use. So you can create any image size in Gimp, but beyond some size, it depends on your patience.

Also, don't overdo it, it you very rarely need to create an image that is bigger than 24Mpx.

(*) Preferences > System resources > Resource consumption > Tile cache size

[PixLab]

(12-27-2023, 09:17 AM)pstein Wrote: I clicked on menu
File--->New
and try to create one with 3000x15000 pixels (see attached snapshot).
Much to my surprise I got a warning popup that gimp will create an image with size of 475 MB.
A simple image with pure white background?
I guess its the uncompressed size (not .png or *.jpg format)

And yes the maximum image size in Preferences is about 128MB

Don't stress about that, GIMP is just telling you some data, personally I did increase this "alert" in the the Preferences to 1/2 GB (soon to be updated to 1GB as I'm working on bigger image), my RAM is 24GB with an old CPU Intel i5-7400 (4 cores) @ 3.500GHz, and all is lightning fast (I'm on Linux)
Those settings you are giving us and the alert you get might go back to an antediluvian age, just confirm YES or OK or/and update your settings like 2/3 of your RAM to be comfy

   

Ummm.... in fact I just updated it because I got too often this kind of alert recently which was annoying me