Samba log file

This has happened a few times more since Dec 7. Disk Capasity is 93 GBytes and I have 73 GByte free space. Suddenly the smbd.log.old appear with all remaining disk space, so there is no more left. I guess there is a fault or broken code somewhere. I need to run smb all the time, so I just remove the odd file. But it is not a good situation. I am too surpriced of no more reports on this one.