I've ran into this problem on a larger scale but lacked the time to investigate it. Now I'm seeing smaller examples on a larger scale and have decided to try to figure it out.
These two computers were imaged from the same DMG and have been in use for a few months. Users have their home folder on another partition, allowing me to nuke the OS partition and reimage it without affecting user data. So nothing the (non-admin) users do should be able to make much of an impact on usable space. My having partitioned the drives (SSDs) means I have a hard limit on space on the system volume, and I'm trying to not use more than I have to, so more is available for the user home folders on the other partition.
This computer has 17gb free:
df -ht /
Filesystem Size Used Avail Capacity iused ifree %iused Mounted on
/dev/disk0s2 93Gi 75Gi 17Gi 82% 19826055 4555238 81% /
du -shx *
4.0K image.txt
47G Applications
436K Creative Cloud Files
4.0K DeployStudio_log.txt
9.4G Library
1.0K Network
5.1G System
4.0K User Information
4.0K Users
2.3G Users_old
4.0K Volumes
2.3M bin
4.5K dev
4.0K etc
1.0K home
4.0K installer.failurerequests
1.0K net
1.3M opt
4.5G private
1.1M sbin
4.0K setup.xml
0B t
4.0K tmp
608M usr
4.0K var
This computer has less than 8gb free:
df -h /
Filesystem Size Used Avail Capacity iused ifree %iused Mounted on
/dev/disk0s2 93Gi 85Gi 7.7Gi 92% 22352334 2028959 92% /
4.0K image.txt
47G Applications
436K Creative Cloud Files
4.0K DeployStudio_log.txt
9.5G Library
1.0K Network
4.8G System
4.0K User Information
4.0K Users
2.3G Users_old
52K Volumes
2.3M bin
4.5K dev
4.0K etc
1.0K home
4.0K installer.failurerequests
1.0K net
1.3M opt
4.5G private
1.1M sbin
4.0K setup.xml
0B t
0B tm
4.0K tmp
608M usr
4.0K var
The question is... WHY? Where did 10 gig of disk space go?
Removing folders with less than 100MB makes it easier to compare
17GB available:
47G Applications
9.4G Library
5.1G System
2.3G Users_old
4.5G private
608M usr
8GB available:
47G Applications
9.5G Library
4.8G System
2.3G Users_old
4.5G private
608M usr
There is a VERY small increase in used space, a few hundred MB, but it's showing a total difference of 10GB.
My only current theory on this is there's a folder somewhere that has a lot of small files in it, and it's the folder size causing this problem. The last time I ran into this, over 100GB of space was missing, and a safe boot fixed it. (and it was NOT due to fsck, I had already repaired the disk, it was deleting temp files or something somewhere)
Ideas?