Slowly Losing Disk Space


Hello to all,

I've noticed in the last few days that I've been gradually, but steadily losing disk space.

I've not downloaded any files bigger than a few Kilobytes (that I've kept) and all my email is IMAP, not POP, so I'm not actually downloading any mails.

A couple of days ago, my disk space available at the bottom of the Finder window said 152.36GB. Today it says 151.45GB.

I've checked my Download directory and other areas for any new data that I might have absent-mindedly downloaded and kept that I don't need, but haven't found anything.

Is there something else I should be checking and clearing from time to time?

Thanks for your help,



U.S.D.A. Prime
Exactly how far is the disk space going down (in megabytes), and over what time period?

"Losing" a few hundred megabytes here and there (and possibly regaining them after a restart) could be chalked up to memory swap space, which is completely normal. However, if you see the disk space drop by a few gigabytes over a short period of time, and that space is never "reclaimed" after a restart, and it continually goes down, then it may be time to investigate further.

Summer Storm

You know, interestingly enough, I've noticed the very same thing. I wasn't looking for it but the fact that I noticed it and now somebody else has, I'm just as curious and baffled. I've never seen this happen on this scale before while running practically nothing that could be attributed to this odd decreasing disk space. Mine is happening in gigs though. It seems the longer my MacBook Pro (early 2008) runs, the more it seems to eat up. For sure, Photoshop CS2 will do this, but it has not been running for some time...perhaps months.

I'm glad it's not just me. I'd be curious to whether you are running any extra System Preferences control panels like NTFS-3G or Plaxo or Fruux, all of these had recent updates. I also would be curious if you are a regular Firefox user, as Firefox was also recently updated. Those are the only new things other than the Apple iTunes update a couple days back.


Chmod 760
Staff member
The space 'loss' of Finder's reported availble space from 152.36GB to 151.45GB sounds like most of that data is simply in caches folder now; HD/users/youruser/Library/Caches or HD/Library/Caches etc. Neither is space lost - they are simply storing some data that will speed the operation in general. You can either check the folder size of HD/users/youruser/Library/Caches manually (this one is probably bigger than the other caches), or most likely get the space back when rebooting. But for only claiming that amount of space back, I wouldn't worry.
OS X will need about 15 % free space on the hard drive for self maintenance. I wouldn't worry for 1 GB fluctuation in reported available space when you'll most likely have more than those 15 % and your system will be clean and healthy.
Cache is the likeliest cause for the reported 'lost' space here. Another possibility would be e.g. if you have put items in Trash - those will still take space until the Trash is emptied.
You can also clean the caches occasionally with a maintenance tool like Onyx. (E.g. when it gets slow, once a month etc)

Hm.. more GBs reported? See if the space comes back after reboot. If it does it was and is cache.
If it doesn't, get a disk/file/directory size reporting application and see where the space is gone.


Thanks for everyone's input. I'm not running any special partitioning or disk formatting; just out of the box OSX.

I'll make a note of overall free space, reboot, and then monitor some more and if the problem persists, I'll dig deeper and come back with my findings.

Thanks, guys!



I had the same problem and downloaded Disk Inventory X to see what was going on and discovered that my itunes library was being saved into an invisible folder on my mac startup disc - MAC HD/VOLUMES/MUSIC... I had used a sync program to keep my external drives up to date on any music additions... anyways, I used Tinker Tool to delete the invisible folder and restored all my drive space back. Just a thought.. and some valuable tool info...

Summer Storm

Interestingly enough, I also discovered that my iTunes was slowly eating away disk space, but it was something I thought I had set up properly. I subscribe to a lot of tech podcast shows like GeekBrief, TekZilla, HD Nation and Cranky Geeks--to mention a few. What I didn't know is that my settings were set to save every episode rather than perhaps the last 2. So, I had piled up close to 45 gigs of old stuff I had no idea was there. I just assumed I had set it up properly and never gave it a second thought. I don't think I would have even discovered this had I not been looking for something else. It was like Christmas and a new hard drive.

So, for those who are subscribing to podcasts in iTunes--especially in HD mode, go check your settings, and then go to the iTunes Media folder inside the main iTunes folder (inside Music) and delete everything and begin again from scratch. I think you'll be surprised what you find.

Now, on the laptop, I only save unwatched shows, so it never fills up. On the desktop, I save the last 2 shows.


Have you looked at the /tmp folder (you'll need to go to a shell and type "open /tmp" (without the quotes) to see it in finder)? It collects files (cleared at the next reboot). A very busy system log could also account to this ... check /Library/Logs or ~/Library/Logs.


The problem is still persisting.

I cleared out a bunch of stuff and deleted another account that was on here that doesn't get used any more and was up to 178GB.

I added some data and applied some updates and that dropped to 175GB.

Since then (that was a few weeks ago) I've been working almost exclusively with text files and now find that I only have 172GB of space left.

I did make a lot of movies when I was on holiday recently, but I burned all that to disk and deleted the original files, so can't understand why this hasn't jumped back to 175GB.

The only thing I've done otherwise is update my iPhone to 4.1 yesterday, but I can't believe that has anything to do with this.

Any suggestions? I'm working back through some of the previous advice, but so far I can't find anything that explains this.


Hi Randy,

Just downloading YASU and will see if that helps.

Doctor X,

I'm not acquainted with TechTools, but will have a look at it now.

Thanks to you both for your help. I really don't know where the problem lies. If it's me and a misunderstanding of something, fine, but I never had this sort of problem with my HP laptop (and I am loathe to say that).

Doctor X

Tech Tools is a diagnostic/repair program that has a "bug" of sorts where it backs up your database . . . and keeps backing it up . . . and backing it up.

However, you do not have it.