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Clear Scratch Disk When It Gets Full on a Mac

30.01.2018

Mac owners often work with various image and video editing software. The choice is wide: from Adobe Photoshop or Premier to Sketch or Final Cut Pro. Both third-party solutions and native tools are great. However, regular work with these apps may lead to the common system errors associated with a “scratch disk” notification. The most typical bug in such situation is that Photoshop rejects to launch.

Luckily, there is a solution to the issue, and the article is going to show you several ways out.

scratch disk full

Defining Scratch Disk

It makes no sense to discuss something without knowing its meaning. Perhaps, you have your best guess, but here is what a scratch disk stands for. It is a space on a hard drive used to temporarily store the data created by media editing software during its work. Adobe Photoshop – as a greatly popular app – is widely known for making use of scratch disks very actively; similar apps do just the same, though. Because scratch disks are only for temporary storage, they serve mostly as the app's virtual or cache memory.

When may Photoshop need a scratch disk? Sometimes, a user is running out of RAM, necessary to complete specific tasks. That is when the app decides to apply one or more scratch disks. Thus, the app is secretly chewing up the computer’s space as it quickly creates numerous temporary files.

Keep in mind that you can assign the scratch disks to one of the available drives (if you have two or more) – and it better be not the startup one. It's usually done while installing or setting up the media editing software.

Techie Layman Explanation of How to Clear Scratch Disk in Photoshop

The “Your scratch disks are full” notification shows up after Photoshop uses up all hard drive space that served as scratch storage. The thing is, the app is supposed to delete created temporary files periodically, but this operation is often skipped due to various reasons. As a result, temp data piles up and clogs the valuable HD space. Here is what a Mac owner can do to clear scratch disks and reclaim gigabytes of space.

Solution 1. Erase the App's Cache

To begin with, media editors usually have built-in tools for clearing caches. Below, we'll provide an example of how to use such utility in Photoshop:

  • Pick the Edit menu button.
  • Dangle around with your mouse over “purge” to display four various features: Undo, Clipboard, Histories, All. The greyed out stuff has been removed.
  • Choose a particular file or ”All” items to erase the cache.
  • This operation cannot be reversed, so decide carefully which cached file/project version you still need and which can be purged. Click OK to confirm the action.

Solution 2. Eliminate Temporary Files

Photoshop’s temporary files is another element that contributes to eating up the scratch disk space. The primary thing to do here is to find the items beginning with “pst,” having a string of numbers and the “.tmp” extension. For that, search your Mac for “Photoshop Temp.”

After the scanning procedure, a Mac owner will be able to view a lengthy list of items. Make sure the current project is saved, and the chosen software is shut down before safely removing the files you do not need.

Solution 3. Weed Out the Unnecessary and Old Files

Getting rid of outdated and large items is always a good method to free up space on a Mac. Don't want to delete them? Well, move this data to external drives or cloud storage.

macOS Sierra and High Sierra users should know that Apple included new features to take care of the disk space. Go to the Apple menu and select About This Mac. Go to the Storage tab to find a Sierra bar graph. Just pick Manage to discover the array of space-reclaiming features. The most useful tool would be an Optimize Storage option. That said, use it only if you completely trust in regular auto-cleaning.

big files in storage

Solution 4. Switch to Another Scratch Disk

You will experience problems with the speed of work and overall computer’s performance once Mac is left with less than 10-15% of free space in reference to the full HD capacity. Many experts may tell that buying a solid-state drive (SSD) might be the best way out, but it might cost a thing, and it has a limited lifespan. Alternatively, you can simply change the scratch disk.

That's how it's done in Photoshop:

  • Select Photoshop menu.
  • Move Preferences-Scratch Disk.
  • Tick the box to choose/delete a drive as the scratch disk.
  • Press OK and relaunch the app.

scratch disk in photoshop

How to Clear Scratch Disk on Mac Using External Software?

Another reliable and simple method to prevent the cache from filling up space is through the regular cleaning. It can be done with the help of built-in macOS utilities, but some users may find it time-consuming and difficult to do. Besides, by clearing Adobe Photoshop cache, you get rid of only a part of all the useless things taking up your disk space. Download and install a special third-party cleaning software to take care of the junk of all types. It will keep your Mac healthy.

MacFlyPro cleaner unobtrusively notifies a user when a computer is about to run out of space. The app will detect the junk files on its own, and the deletion process will become a matter of several clicks. MacFly Pro will display the scanning results to let the Mac owner decide which items should go and which can stay in the system. You can download and start using the app here.

At least one of the described methods will assist in overcoming issues with the scratch disks. No matter whether you prefer manual approaches or third-party cleaning software like MacFlyPro, you will face a fantastically smooth Photoshop and speedy Mac!


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