6.x loosing record of free space after filesystem fills?

Guy Helmer ghelmer at palisadesys.com
Tue Nov 28 08:49:19 PST 2006

We're encountering some problems on FreeBSD 6.1 SMP with a number of 
end-user systems where a Postgresql database is growing to the point 
where the filesystem is nearly full or completely runs out of free 
space.  After this point, df shows wildly incorrect values for available 
space, sometimes even showing more space available than there allocated 
to the partition (and our systems rely on df to determine when to send 
warnings to end-users that the free disk space is getting low).  We've 
found the only way to correct the situation is to take the system down 
to single-user mode and force a non-background fsck on the partition - 
simply rebooting the system does not fix the situation.

We're going to try setting debug.mpsafevfs to 0 in /boot/loader.conf to 
see if this works around the problem.  I've gone through the CVS logs 
for src/sys/ufs/ffs/* but I haven't seen anything that would 
specifically apply to this problem.  Has anyone else seen this problem, 
and by chance is it resolved for 6.2?


Guy Helmer, Ph.D.
Chief System Architect
Palisade Systems, Inc.

More information about the freebsd-stable mailing list