Acorn all but froze completely

A very scary thing happened to me yesterday. I opened an old file I had created using an early version of Acorn on my old '09 iMac. The image has about a dozen layers. I copied one small selection from the top layer, then created a new file using the copied image. I actually made 3 layers on this new file then tried to create a text on the top layer.
Things got very difficult from then on. Whatever I clicked on, either within the text tools pallet or on the image, took ages to activate. In the text pallet a mere click would produce the ‘beach ball’, not spinning, for about 10 second, followed by the cursor missing for another dozen seconds.
Trying to adjust settings in the text pallet was just about impossible. I eventually gave up and decided to shoot myself instead. But it’s okay, I don’t have a gun. :joy:
Now admittedly I only have 8 Gigs of memory in this machine, and admittedly I’m no computer guru, so I don’t know if this is relevant. My old machine has 16 Gigs. I asked my Mac guru if he would put 16 Gigs into this one, to accommodate my extensive imaging activities (some of my files have 30-odd layers), but he said it’s a very tricky operation with this model and he wouldn’t like to risk damaging the mother board. Besides, he said, 8 Gigs is ample alongside the 1 TB internal SSD that he installed for me.
Strangely, this morning when I opened the new image file with it’s 3 layers, everything seemed back to normal. I was able to make alterations and add new text layers to it.
But I’d love to know what caused yesterday’s fiasco, and if it’s likely to happen again. Any comments or suggestions anyone? (about the problem I mean, not about getting a gun!) :smiley:

Actually I was mistaken, the image I opened yesterday has 29 layers - but there’s not an awful lot on each layer! :grimacing:

In case I didn’t explain very well, the 29 layer image was created years ago on a 2009 iMac with 16 Gigs of memory, but my troubles yesterday happened when I opened that image on a 2017 iMac with only 8 Gigs of memory.

It really depends on the size of the image. Faster computers with more memory are always going to be better - but you didn’t mention what the pixel dimensions of the image were.

If it was a 100x100 pixel image with 29 layers, Acorn should be able to handle that without even thinking about it.

If it was a 5120x2880 pixel image (14 megapixel), with 29 layers, that’s at least 427,622,400 pixels to work with, and 1.6GB of memory is needed to hold those layers - and that’s without considering undo & scratch surfaces which are needed. So it just really depends on what you’re doing.

It also depends on how many other apps you have open, and how much memory those might be taking up. If most of them 8GB of memory is taken up by other apps, then that doesn’t leave Acorn much to work with.

Thanks a lot for your helpful reply Gus. So it looks as if I was right in that I do need all the ram I can squeeze in.
That file I opened the other day is 2520 x 3777, and taking up 43.6 Mb. Does a layer with very little on it take up as much memory as one with lots of coloured imagery? If so, I guess it’s every pixel for himself in 'puter land.
Be that as it may, some of the files I’ve worked on in years gone by have been colossal compared with this 43 Mb one. Makes me wonder how the veteran iMac handled it without bursting.
The long and the short - I guess I really need to insist on getting the maximum memory squeezed into this 2017 iMac.
Thanks again.

A quick tip - a while back I added a feature to Acorn where you can quickly see how many layers you have, total pixels between all of them, and the amount of memory those layers are taking up.

All you have to do is press the ‘v’ key twice (like a double click) and a palette will come up with that info and more.

It depends on a number of factors, but Acorn does its best to keep the memory usage down.

Thanks for the tip Gus, that’s a very helpful feature. And it shows the 29 layer file I opened the other day was only 1.99 Gigabytes. So I guess I can’t lay any blame on Acorn, it must have been something nasty happening elsewhere in this mysterious machine.