Photoshop using massive amount of disk space when opening a PSD and then scratch disks are full

[jonw84637587]

I've got 45gb of free space on my scratch disk, the moment I open photoshop it drops down to around 25gb, and then when I open a certain file that drops down to 11gb. And then when I try to do anything on that file Photoshop just throws up the Scratch Disks are full error. The file I'm opening is relatively big, but less than 1gb.

Why does this happen and what can I do to prevent it?

[c.pfaffenbichler]

What have you done for Photoshop Performance so far? 

https://helpx.adobe.com/photoshop/kb/optimize-photoshop-cc-performance.html

https://helpx.adobe.com/photoshop/using/scratch-disks-preferences.html

Can you assess a larger Scratch Drive? 

The filesize on disk is not exactly the relevant measure as psd/psb files are compressed by default. 

What are the image’s pixel dimensions, Color Mode and bit depth? 

[D Fosse]

This is expected. You simply don't have enough scratch disk space, get more.

Most people underestimate the free disk space needed for Photoshop's scratch disk. The official system requirements are just enough to install (and maybe open) the application, but for serious work you need orders of magnitude more.

Raster image editing moves huge amounts of data around, and it needs to go somewhere. There is no such thing as "enough RAM", no matter how much you have installed.

For most normal situations, 250 GB free space should be considered absolute minimum. If you're working with large files, or many files open at the same time, 500 GB to 1 TB is more realistic.

[jonw84637587]

I respectfully disagree that this is expected requirements that I need to have 250gb at a minimum when I've been using Photoshop 2021 daily since it was released, and only recently has this started coming up.

My MacBook Pro only has 250gb in total as available space, I don't think it's unreasonable for me to be of the expectation that I should be able to open a large, but not outrageously so, .PSD file and be able to use any functionality at all without thinking "I need to literally delete everything else on my hard drive to run this."

[c.pfaffenbichler]

Have you bothered reading the page on Scratch Disks? 

What are your Performance and Scratch Disk Preferences settings? 

[jonw84637587]

Ah sorry, I had a reply written out to your previous comment c.pfaffenbichler.

Yes, I did bother to read both of those articles, I stepped through them before I posted here.

Firstly I tried the 3 different presets for optimising photoshop, and then incrementally allocated memory until I had allocated 100% of my available RAM. Photoshop as of time of posting this can use 12604MB of ram, has a max number of 20 in it's history, has 6 cache levels, and the tile size 1024k.

My Scratch Disk uses my laptops HDD, which is 250gb. When I open Photoshop it displays 25gb free space, then when I open this particular PSD file it drops down to 11 and becomes completely unusable.

The file itself is ~800mb, contains 8 art boards, each artboard is 2676 x 19736 pixels at 72 resolution in RGB.

[c.pfaffenbichler]

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The file itself is ~800mb, contains 8 art boards, each artboard is 2676 x 19736 pixels at 72 resolution in RGB.

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So assuming 8bit that would be 151,1MB times 8 right off the bat without doing anything – but probably more; after all what are the pixel dimensions of the image, not the artboards? And how about the Layers? And are Smart Objects involved? 

As mentioned previously the filesize on disk is not particularly relevant because it can benefit from compression. 

[D Fosse]

incrementally allocated memory until I had allocated 100% of my available RAM.

By @jonw84637587

Never do that. Other applications and processes need memory too. Even plugins like ACR run outside Photoshop's address space and require their own memory separate from Photoshop.

You can disagree if you will, but 25 GB free space for the scratch disk is next to nothing. I can use up 25 GB in thirty seconds.

A 20 000 pixel file is big by any standards. You need to make sure Photoshop has enough resources to work with it.

[Earth Oliver]

are there any embedded smart object on the artboards?

[davescm]

It happens because Photoshop uses temporary disk space (i.e. scratch space) as an extension to working memory. How large the scratch disk grows depends on the file(s) in use, the content of those files e.g number of layers , smart objects, history states , and what functions are being executed on the files. It is not uncommon to see the scratch disk file go larger than 100GB regardless of available RAM size (I have 128GB RAM here and Photoshop still needs plenty of scratch disk space).

Dave