Huge quota.group file

[Artem Kuchin]

Hello!

Today i noticed second time that quotarep run 100% of CPU for crazy 
amount of time.
I killed it. Then checked /quota.group file
It is over 40GB in size

Tried googling about such problem and found only that quota.group 
becomes crazy huge
when there are files with unknown group and that i should find such file 
using

find / -nogroup >filelist_group.txt

fix group on them and rerun checkquota

But i cannot do it because i am running several jails and using quota 
from host but jails
have their own group and users.

Still, i i don't understand why such crazy behavior.

Any comments or suggestions of this?
Also, how to reinit quota.group with rebooting?

FreeBSD XXX 10.2-STABLE FreeBSD 10.2-STABLE #1 r293034M: Sat Jan  2 
14:55:41 MSK 2016     XXX at XXX:/usr/obj/usr/src/sys/OMNI  amd64

Artem