FreeBSD 9: Group quotas increase but don't decrease automatically

[Adam Strohl]

I'm running FreeBSD 9 on a number of systems and finally decided to take 
advantage of the quota system to enforce limits on my users.

No real issues setting it all up aside from finding that 
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/quotas.html 
needs to be updated.   The new /etc/rc.conf entry is quota_enable="YES" 
not enable_quotas="YES" as it says (assuming it used to be this in 
8.x?).  I'll file a PR for this shortly.

I did however run into a more serious issue (I think):

A group or user's allocation as reported by repquota(8) will increases 
with new/growing files, however when a file is deleted or chgrped out of 
the quota's group, the amount of space reported by repquota(8) does not 
decrease.  I have verified that the system does not register the freed 
space by going over the soft limit, being denied write, then deleting 
files.  Even if I delete files which drop me below the soft quota limit, 
I will not be able to add them as I am still "over quota".    So it does 
not appear to be reporting issue, the system really doesn't realize the 
usage has gone down.

Interestingly the inode counts do decrease automatically/"instantly" as 
I would expect.

Running quotacheck(8) fixes the issue and updates the allocation counts, 
but does not magically fix auto-updating, so needs to be done 
periodically which can be a bit intensive depending on file count.

I see this on all FreeBSD 9 machines with quotas turned on.

For now I have a cron script which tries to guess (based on changing 
inode counts, etc) if it should run quotacheck, and does so if needed 
(to avoid just blindly running it periodically).

Anyone else run into this?  Am I missing something?  Known issue?  Let 
me know if anyone wants more info, etc.   I can also paste the work 
around "smart" cron script if anyone is interested (and I'm not missing 
something silly :P).


-- 

Adam Strohl
A-Team Systems
http://ateamsystems.com/