Strange results after partition-full condition...

[Karel J. Bosschaart]

On Tue, Jul 29, 2003 at 12:55:26AM +0200, Garance A Drosihn wrote:
> I have a test 4.x-stable system that I recently rebooted into.
> The last time I had updated it was May 3rd.  I cvsup'ed it,
> did the buildworld/installworlds, and everything seemed fine.
> 
> I then thought I would update all the ports.  When upgrading
> XFree86, the /usr partition ran out of disk space.  Now the
> partition shows up as:
> 
> (21) df -k
> Filesystem  1K-blocks    Used   Avail Capacity  Mounted on
> /dev/ad0s2a    251950   35550  196244    15%    /
> /dev/ad0s2f    241870      10  222512     0%    /tmp
> /dev/ad0s2g   2064302 -164180 2063338    -9%    /usr
> /dev/ad0s2e    257998   61258  176102    26%    /var
> /dev/ad0s2h   1311026  676644  529500    56%    /Users
> 
> This has persisted through a bunch of 'sync's and a system
> reboot.  Actually it had started as -1% capacity, but went
> to -9% as I removed files (like all of /usr/obj/usr/src ).
>
A while back I've also seen weird numbers on one of my 
partitions: despite that minfree was 8% (default) the "Capacity"
went to ~130%, and the "Used" part became larger than the number
of 1K-blocks. This was on -stable, soft-updates enabled. 'sync's
didn't have any effect either.

> I have some other process running right now, but when that is
> done I'm going to shutdown and then run fsck on that partition.
> I assume that will clear it up.
> 
Yes, in my case it solved the problem.

> This is on a dual-CPU system, if that is significant.  The
> partition is mounted:
>      /dev/ad0s2g on /usr (ufs, local, soft-updates)
> 
> This is only a test system, so it isn't much of a problem for
> me.  I just thought that it was odd enough that I should
> mention it.  Has anyone else seen behavior like this?
>
I've seen it, but no idea how to reproduce above situation. 

I don't know if it is related, but when using a USB flash drive
(UFS formatted, no soft-updates, minfree=0), I often see after
mounting that the free space is incorrect; it shows the free space
it had before I deleted some files, during a previous mount.
Unmounting and fsck'ing solves it. Usually it happens when the stick
is unmounted in -stable and mounted on -current. Although mounting
in -stable shows the correct numbers, an fsck (also on -stable)
reveals "SUMMARY INFORMATION BAD". Is this an indication that the
filesystem was left in a dirty state? Both -stable and -current
mount it anyway, but only on -current it is evident from the 
numbers that something is wrong.
(After unmounting I always wait some time before disconnecting 
the flash drive, at least until the LED doesn't flash anymore, 
but usually much longer).

Karel.