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macrlz9

macrumors 6502a
Original poster
Dec 6, 2003
625
130
Illinois
So I use Parallels to run 10,12, 10.13, & 10.14 VMs. I keep them 100% plain vanilla install, only installing the regular OS updates. I use these VMs for testing & always make a snapshot before testing & restore back once done to keep the VM clean.

I've noticed that these VM's all seem to be ballooning in size. For example, my Mojave VM size is 29.13GB, About This Mac reports 15GB used, Macintosh HD Get Info & Disk Utility show 24.97GB used with 9.98GB purgeable.

If I've never installed any applications, created any files, etc, what is purgeable? I am not signed into iCloud, this is a basic install with no 3rd party apps or files added. I don't expect the space used reported by the guest OS & the actual PVM file size to match but the discrepancy of nearly 10GB within the guest OS is what is confusing me.

The other VMs for Sierra and High Sierra feature similar discrepancies regarding the purgeable space. How do I find out what this is and clear it out?

Screen Shot 2019-04-04 at 2.57.37 PM.png Screen Shot 2019-04-04 at 14.59.12.png
 
I am not using Parallels, but VMwae has the same issue on macOS guests.
Windows files systems can be "shrunk," but the only solution for macOS I found is:
1. Create a second virtual sparse disk.
2. Use Carbon Copy Cloner to clone the guest system inside the running VM.
3. Boot form the clone.
4. Remove and delete the original disk.
 
I am not using Parallels, but VMwae has the same issue on macOS guests.
Windows files systems can be "shrunk," but the only solution for macOS I found is:
1. Create a second virtual sparse disk.
2. Use Carbon Copy Cloner to clone the guest system inside the running VM.
3. Boot form the clone.
4. Remove and delete the original disk.

That’s a very good idea, I will have to give it a try! It’s a shame this needs to be done in the first place but glad to have a possible workaround. Thanks for that.

Clean my mac claims to be able to clear this pursuable space...
https://setapp.com/how-to/how-to-clear-purgeable-space-on-macos

I actually found that article and tried Clean My Mac. It did find some space to free up but very little. I assume it’s because there are no files or optimized iCloud data for it to free up. Thanks for the suggestion!
 
To be fair, Windows clients have same issue in virtual environments. For example, I use VirtualBox for a Windows 10 VM, and it grows as well. Need to run old Windows sdelete program to zero out unused blocks, then use a VirtualBox command line program to compact the virtual disk.

Quick scan of Parallels' support site, seems like they too have a command line program that has a "compact" option (it's buried in the .app folder). Also, there might be a switch to enable TRIM on the virtual disk (something to maybe try). And there is a "Reclaim" option under the File menu where you can select a vm and reclaim disk space (or sit it is implied).
 
To be fair, Windows clients have same issue in virtual environments. For example, I use VirtualBox for a Windows 10 VM, and it grows as well. Need to run old Windows sdelete program to zero out unused blocks, then use a VirtualBox command line program to compact the virtual disk.

Quick scan of Parallels' support site, seems like they too have a command line program that has a "compact" option (it's buried in the .app folder). Also, there might be a switch to enable TRIM on the virtual disk (something to maybe try). And there is a "Reclaim" option under the File menu where you can select a vm and reclaim disk space (or sit it is implied).

Have you tried the options in this article?

https://www.howtogeek.com/304555/how-to-free-up-disk-space-in-parallels/

I'm interested as I've seen this issue as well.

I did try the command line prl_disk_tool utility to compact the disk, it didn't make a difference. TRIM is enabled for the virtual disk & the "Free Up Disk Space" option says "No reclaimable disk space found".

I want to point out that I don't believe this to be an issue on the Parallels/Virtual Machine disk image side as it closely matches the size being reported as used by the Guest OS. My issue is my Guest macOS Mojave Virtual Machine is reporting nearly 10GB of "purgeable" storage and I don't know why. Let's forget that this is a virtual machine altogether & say it's a regular install on a Mac, how would one reclaim the "purgeable" storage?

As NoBoMac mentioned, my Windows VM's don't have this issue as the Windows Disk Cleanup utility does a good job of clearing out temporary files, old installers, etc & the reported disk usage more closely matches the size that the actual Virtual Machine file takes up.
 
I am not using Parallels, but VMwae has the same issue on macOS guests.
Windows files systems can be "shrunk," but the only solution for macOS I found is:
1. Create a second virtual sparse disk.
2. Use Carbon Copy Cloner to clone the guest system inside the running VM.
3. Boot form the clone.
4. Remove and delete the original disk.

Just wanted to update and say that I tried your suggestion and am AMAZED! The virtual machine file went from 29GB to 14GB, HUGE difference. I was also impressed with how quick CCC was to clone the disk...

Between all of my VM's, your suggestion helped me free up 65GBs! woo hoo!
 
Last edited:
Clean My Mac JUST added the ability to clear pursuable space.
It seemed to clean up non recent iCloud drive downloads, and leaving previously downloaded files as the file with the download link again.. very cool. I've wanted this for a while... I've been downloading large files from iCloud drive via web browser so I don't have a download file that I have to keep or delete.
 
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