So how much disk space have I actually got?

[Applelad]

I have a Crucial M500 SSD 960GB SSD and seem to be missing about 60GBs

Disk utility says it's 960.2GB and Finder reports 289.55 GB free - after emptying my trash.

Disk Inventory X when measuring logical file sizes says I've used 604GB, have 269.7GB Free and 23.5 GB Other - giving a total of 897.2 GBs

Disk Inventory x when measuring physical file sizes says I've used 600.7GB, have 269.7GB Free and 23.5 GB Other - giving a total of 893.9 GBs

OK, so there's not much difference between Logical and Physical sizes so I can rule that out as being the cause of my missing GBs.

I have two other user accounts (test accounts with not much in them) on the machine that Disk Inventory X seems unable to read the user specific folders of when running under the main user of the machine. However, I've checked these by running Disk Inventory X while logged in under each other user and one has an additional 6GBs and the other 10GBs. So even if this is part of the cause of the missing GBs it still means I'm missing about 40GBs somewhere.

I know in the grand scheme of things it's not that much but it's enough to worry me that there might be 40GBs of stuff that I just can't see on my computer and I have no idea what it is - or the disk just isn't as big as Crucial say it is!

Edit: I've also just looked at the disk using Disk Drill Pro and that says the drive is 894.25GBs in size and also looked at tit in TechTool Pro which says it's 959.85GBs in size!!!!!!

Any ideas

 

[h9826790]

Are you sure that you always looking at the disk size, but not the partition size?

 

[Weaselboy]

I have a Crucial M500 SSD 960GB SSD and seem to be missing about 60GB.

Do you have Time Machine turned on? TM uses hidden local snapshots and that can take up some space. Most of these disk space utilities will not show this hidden space.

sudo du -d 1 -x -c -g /

Enter this command in Terminal and wait for it to complete and it will show all the base folders with space used in GB by each one. Look for one called /.Mobilebackups and that is the Time Machine hidden folder. You can zero it out by turning TM off then back on.

 

[Applelad]

In response to both you guys, I have no partitions on the disk and Time Machine is switched off (and it's never been switched on). I'm stumped.

 

[Weaselboy]

In response to both you guys, I have no partitions on the disk and Time Machine is switched off (and it's never been switched on). I'm stumped.

Run that command anyway and it will show you where your space is being used.

You also might try a command-r boot to recovery and use Disk Util to run repair disk to see if that picks up any errors.

 

[chabig]

It's very simple. Crucial defines 1 GB as 1,000,000,000 bytes. This is the accepted definition of a Gigabyte. Mac OS, including Finder and Disk Utility use this definition too.

Disk Inventory and Disk Drill Pro define 1 GB as 2^30 bytes = 1073741824bytes. This is accepted definition of a Gibibyte, not a Gigabyte. Historically, storage was measured in powers of 2, and not everyone has accepted the new definitions.

960 Gigabytes bytes is the same as 894 Gibibytes. You aren't missing anything.