File System shows 100% occupied but du tells different and still has Unused Spaces.

We have faced an issue as below mentioned – found /oracle mount-point showing 100% as Used. But getting different size values for folders under /oracle mount-point, when we executed du -gs .

bash-4.4# df -g
Filesystem GB blocks Free %Used Iused %Iused Mounted on
/dev/hd4 4.00 1.39 66% 20686 6% /
/dev/hd2 4.00 1.02 75% 45679 16% /usr
/dev/hd9var 2.00 1.01 50% 16318 7% /var
/dev/hd3 2.00 1.83 9% 407 1% /tmp
/dev/hd1 1.00 0.16 85% 6124 12% /home
/dev/hd11admin 0.25 0.25 1% 5 1% /admin
/proc – – – – – /proc
/dev/hd10opt 0.50 0.07 87% 12979 44% /opt
/dev/livedump 0.25 0.25 1% 4 1% /var/adm/ras/livedump
/dev/fslv00 198.00 0.01 100% 440205 16% /oracle

bash-4.4# cd /oracle/
bash-4.4# du -gs *
0.00 AutoDeployment
5.45 Oracle
0.03 Patch
7.54 data01
11.67 fmw_12.1.3.0.0_wls
0.01 jboss
0.20 jdk
0.00 lost+found
0.92 wls1221

You may notice 100 % utilization for /oracle mount-point on the “df -g” output , but with “du -gs ” We found the files did not occupy the entire space.

It may be because of open files in the file-system. These open files hold space on the file-system to complete there execution, once the write operation is completed. 

To overcome, from this issue, We need to follow below two steps:-

1. We need to find all such processes still running but using deleted files, in result – /oracle mount-point is showing 100% as Used.

bash-4.4# fuser -dV /oracle/
/oracle/:
inode=670047 size=5242722 fd=389 5570776
inode=1165305 size=20278 fd=1 8061106
inode=1165313 size=182335565824 fd=1 8716486
inode=1165305 size=20278 fd=1 9044152
inode=1165313 size=182335565824 fd=1 9371672
inode=1165305 size=20278 fd=1 11141354
inode=669981 size=5514335 fd=1 13041898

2. We have to kill all such processes as found in above command.

bash-4.4# kill -9 5570776
bash-4.4# kill -9 8061106
bash-4.4# kill -9 8716486
bash-4.4# kill -9 9044152
bash-4.4# kill -9 9371672
bash-4.4# kill -9 11141354
bash-4.4# kill -9 13041898

bash-4.4# fuser -dV /oracle/
/oracle/:

bash-4.4# df -g
Filesystem GB blocks Free %Used Iused %Iused Mounted on
/dev/hd4 4.00 1.39 66% 20686 6% /
/dev/hd2 4.00 1.02 75% 45679 16% /usr
/dev/hd9var 2.00 1.01 50% 16318 7% /var
/dev/hd3 2.00 1.83 9% 407 1% /tmp
/dev/hd1 1.00 0.16 85% 6124 12% /home
/dev/hd11admin 0.25 0.25 1% 5 1% /admin
/proc – – – – – /proc
/dev/hd10opt 0.50 0.07 87% 12979 44% /opt
/dev/livedump 0.25 0.25 1% 4 1% /var/adm/ras/livedump
/dev/fslv00 198.00 170.01 15% 440205 1% /oracle
bash-4.4# cd /oracle/
bash-4.4# du -gs *
0.00 AutoDeployment
5.45 Oracle
0.03 Patch
7.54 data01
11.67 fmw_12.1.3.0.0_wls
0.01 jboss
0.20 jdk
0.00 lost+found
0.92 wls1221