If you’ve ever experienced your Photoshop working slowly, whether that’s when processing large images or other edits, you can change the amount of RAM the program eats up
To do this, go to Preferences>Performance, which, if you’re using a Mac, is found under the Photoshop menu. For Windows users, go to the Edit menu.
Under the Memory Usage section, you’ll see a slider that shows the percentage of available megabytes Photoshop is using.
Compare Available RAM to Ideal Range. If you use only Photoshop and no other programs, then you can afford to set this to a high percentage to speed up things up.