Excessive disk space usage

[Wrivium]

When I turn on my PC, my SSD has 150GB of free space. But when I start working in Photoshop, this free space drops to 80GB, almost 50%.

I don’t remember this happening before, and it seems crazy that it takes up so much disk space while in use.
Is there any way I can restrict this like in the past when it only used around 20GB?

[D Fosse]

This is normal. It's not Photoshop - it's the amount of data it needs to manage. You probably have more history states than before; that's the main part of the scratch file. Or bigger files, or both.

Total memory requirement vastly exceeds the amount of RAM you may have installed. So working data are written to disk - aka the scratch disk. Think of the scratch disk as Photoshop's main memory, with RAM as a fast access cache holding the most current data.

The scratch file contains all history states for all open documents, plus overhead for some special functions. Each history state potentially adds the full uncompressed file size.

The general advice is to have at least 200 GB free disk space for the scratch disk. For big files more - personally, I'm not comfortable with anything less than 500 GB (in reality I have several TB).

If you're forced to work with limited disk space, reduce the number of history states.

[Wrivium]

Currently, I have 64GB of RAM. Do I need more than that? In Performance, I set it to use around 20GB of RAM.

I also configured the Scratch Disk to distribute the used space across the other drives, although it seems that isn't having any effect.

[D Fosse · Accepted solution]

Actually, RAM isn't critical. As I said, there's not "enough" under any circumstances. Set RAM usage to 70 % in Preferences (always leave enough for the rest of the system), and you'll be fine. The scratch disk is much more important.

Whether spread over several drives or all on one shouldn't matter all that much - but the faster the drives, the better. This has quite a bit of impact on Photoshop performance. In most cases the system drive will be the fastest.

[Wrivium]

Thank you!
I guess I'll have to buy another SSD then