When deleting a large files, the file is deleted successfully but the size of the filesystem does not reflect the change.
The files was be deleted, but only restarting the jvm or java process released the disk space.
Usually occurs with log files.
The lsof command show the files opened in system.
For example: lsof |grep deleted
java 15138 oracle 2959r REG 253,3 5875027 131163 /logs/soa_domain/WLS1_SOA1/WLS1_SOA1.out03422 (deleted)
java 15138 oracle 3054r REG 253,3 10480928 131166 /logs/soa_domain/WLS1_SOA1/WLS1_SOA1-diagnostic-81.log (deleted)
java 15138 oracle 3062r REG 253,3 10479417 131200 /logs/soa_domain/WLS1_SOA1/WLS1_SOA1-diagnostic-82.log (deleted)
The command output shows pid, owner, file descriptor (fd), size and file.
If can’t restart the process, it is possible to force the system to de-allocate the space consumed by an in-use file by forcing the system to truncate the file.
$ echo > /proc/pid/fd/fd_number
Be careful not to truncate unwanted files.
In my case:
$ echo > /proc/15138/fd/2959
$ echo > /proc/15138/fd/3054
$ echo > /proc/15138/fd/3062
That’s all for today.