Perplexed about my SSD storage

[jingletido]

I have 3 macs all running ElCapitan. Two are iMac desktops and one is a macbook air. They are all fairly new and all were purchased with 500 GB Flash drives (not fusion). All three computers are running the same programs and apps. Both the iMacs have lots of storage still available (about 250GB each). But the Mac Book Air is almost out of storage. I'm getting warnings on the Air that dropbox can't sync because I don't have enough space. There is only about 18 GB of storage available on the Air.
But it doesn't make sense, because the macbook air doesn't have anything additionally installed or any files/programs more than what is on the two iMacs.
Is there an explanation for this?
Thank you!

 

[Mr_Brightside_@]

http://grandperspectiv.sourceforge.net

 

[IowaLynn]

Connect to TimeMachine or turn TimeMachine backups off for the MBA is my first guess.

Use an app to look at storage usage.

 

[Fishrrman]

Agree with post above to TURN OFF TM backups, probably eating up a lot of space.

Also, this is better than Grand Perspective or ANY of the "visual-oriented" apps insofar as determining what folders and files are eating up your drive space:
Diskwave, which can be found here:
https://diskwave.barthe.ph

Just download it and open it.
You'll see what to do next.
TIP: in the preferences, TURN ON the option to show "normally invisible" files...

 

[jingletido]

Thank you all for your suggestions. I have Time Machine backing up to an external drive, so I don't understand how Time Machine would be eating up space on my internal SSD drive of the MacBook Air. Am I understanding correctly that Time Machine may still be utilizing storage space on my internal drive, even though the backups are going to another external drive?

 

[Alrescha]

I don't understand how Time Machine would be eating up space on my internal SSD drive of the MacBook Air

If Time Machine is unable to back up to the external drive, it will create a local copy of the data to be backed up - some protection is better than none at all. Rarely, Time Machine can get confused and not delete this data. Turning off Time Machine may help clean things up if this is the case.

For more details, see: https://support.apple.com/en-us/HT204015

A.

 

[chown33]

Thank you all for your suggestions. I have Time Machine backing up to an external drive, so I don't understand how Time Machine would be eating up space on my internal SSD drive of the MacBook Air. Am I understanding correctly that Time Machine may still be utilizing storage space on my internal drive, even though the backups are going to another external drive?

This is how Time Machine uses your Air's internal drive:
https://support.apple.com/en-us/HT204015

So the question is: when was your last TM backup from the Air to the external drive?

Also, you can disable the TM snapshots. See here:
http://pondini.org/TM/30.html

EDIT: ninja'ed by Alrescha

 

[jingletido]

This is how Time Machine uses your Air's internal drive:
https://support.apple.com/en-us/HT204015

So the question is: when was your last TM backup from the Air to the external drive?

Also, you can disable the TM snapshots. See here:
http://pondini.org/TM/30.html

EDIT: ninja'ed by Alrescha

ahhh... understood. Thank you again very much!
[doublepost=1458598116][/doublepost]

If Time Machine is unable to back up to the external drive, it will create a local copy of the data to be backed up - some protection is better than none at all. Rarely, Time Machine can get confused and not delete this data. Turning off Time Machine may help clean things up if this is the case.

For more details, see: https://support.apple.com/en-us/HT204015

A.

I always learn good stuff here. Thank you!

 

[pedrom]

I don't get this. You could easily understand what was going on by going to  - about this mac - storage. What's the deal?

 

[Weaselboy]

I don't get this. You could easily understand what was going on by going to  - about this mac - storage. What's the deal?

Because that Storage readout is almost always wrong and is worthless.

=========

OP> I agree with the others posts it is likely the Time Machine local snapshots using up some space.

If you run the command below in Terminal it will show you how much space that hidden folder is using.

sudo du -hs /.MobileBackups

 

[jingletido]

Because that Storage readout is almost always wrong and is worthless.

=========

OP> I agree with the others posts it is likely the Time Machine local snapshots using up some space.

If you run the command below in Terminal it will show you how much space that hidden folder is using.

sudo du -hs /.MobileBackups

Again, I thank you for figuring out the problem. I got rid of those mobile backups and that freed up lots of storage. Problem solved. Thanks to all.