Strange Out of disk space

[Nejc Škoberne]

Hey,

>> My guess is that something has mmap-ed a HUGE chunk of
>> disk space. If I reboot the space is freed.
> 
> Much more likely is that some program has deleted a large file, 
> while still holding it open.  Usual suspect is some kind of log file,
> or temporary file.

I also had a similar problem, which I solved right now. :) So thanks for the inspiration
to try harder to find out what was eating my disk space. df showed this:

/dev/mirror/gm0s1f 112291390 83438178 19869902    81%    /usr

and "du -d1 -k /usr" showed:

46934133        /usr

When this happened before, everything was freed after reboot.

Just now, when writing this post, I went through my process list (I wanted to compare
running services with your system) and found this:

  2131  ??  DL     3:36,42 [md4]

Then I remembered that once, quite some time ago, I created a file-backed filesystem
using mdconfig. I did "mdconfig -l -u /dev/md4" and got this:

md4     vnode     111G  /usr/snapshot/snap

Because /usr/snapshot/snap doesn't exist anymore (I remember deleting it one day,
because I thought I didn't need it anymore), du shows wrong size.

Then I just did "mdconfig -d -u /dev/md4" and everything is OK now:

/dev/mirror/gm0s1f 112291390 46935874 56372206    45%    /usr

Hope that it maybe helps. :)

Bye,
Nejc