NAME

       defragfs.ocfs2 - online defragmenter for ocfs2 filesystem

SYNOPSIS

       defragfs.ocfs2 [-c] [-v] [-l] [-g] [-h][target]...

DESCRIPTION

       defragfs.ocfs2  reduces fragmentation of ocfs2 based file. The file targeted by defragfs.ocfs2 is created
       on ocfs2 filesystem The targeted file gets more contiguous blocks and improves the file access speed.

       target is a regular file, a directory, or a device that is mounted as ocfs2 filesystem.  If target  is  a
       directory, defragfs.ocfs2 reduces fragmentation of all files in it. If target is a device, defragfs.ocfs2
       gets the mount point of it and reduces fragmentation of all files in this mount point.

OPTIONS

       -c     Print the numbers of files that should be processed

       -v     verbose  mode,  the  current fragmentation count and the ideal fragmentation count are printed for
              each file.

              If this option is specified, target is never defragmented.

       -l     defragfs.ocfs2 will run in low io mode, which means it will regularly yield  cpu  to  allow  other
              processes to run.

       -g     defragfs.ocfs2  regularly records the current progress. So if it is interrupted, the next time you
              run defragfs.ocfs2 with this option, it will resume from the recorded progress.  Note that if this
              option is specified, other options are ignored and replaced by those that were recorded.

       -h     Print help info

NOTES

       defragfs.ocfs2 does not support files in lost+found directory. When target is a device or a mount  point,
       defragfs.ocfs2 doesn't defragment files in mount point of other device.

       It  is  completely  not  recommended  to  run against a file while it is actively in another application.
       Since the read/write of a file involves a dlm lock, this can result in a  performance  slowdown  to  both
       defragfs.ocfs2 and the application due to contention.

       If  the  file  system's  free  space  is  fragmented,  or  if there is insufficient free space available,
       defragfs.ocfs2 may not be able to improve the file's fragmentation.

       Non-privileged users can execute defragfs.ocfs2 to their own file.  Therefore,  it  is  desirable  to  be
       executed by root user.

AUTHOR

       Written by Larry Chen <lchen@suse.com>

Version 1.8.7                                     January 2012                                 defragfs.ocfs2(8)