LSSU(1)                     General Commands Manual                    LSSU(1)

       lssu - list usage state of NILFS2 segments

       lssu [options] [device]

       lssu is a utility for displaying usage state of NILFS2 segments in
       device, where a segment is contiguous lump of disk blocks and an
       allocation unit of NILFS2 disk space.  When device is omitted,
       /proc/mounts is examined to find a NILFS2 file system.

       This command will fail if the device has no active mounts of a NILFS2
       file system.

       -a, --all
              Do not hide clean segments.

       -h, --help
              Display help message and exit.

       -i index, --index=index
              Skip index segments at start of input.

       -l, --latest-usage
              Print usage status of the moment.

       -n lines, --lines=lines
              List only lines input segments.

       -p period, --protection-period=period
              Specify protection period.  This option is used when printing
              usage status of the moment (with -l option) to test if each
              block in segments is protected and is not reclaimable.
              Optionally, the period parameter may be suffixed by one of the
              following units designators: ´s´, ´m´, ´h´, ´d´,´w´,´M´, or ´Y´,
              for seconds, minutes, hours, days, weeks, months, or years,

       -V, --version
              Display version and exit.

       Every line of the lssu output consists of the following fields:

       SEGNUM Segment number.

       DATE   Creation date.

       TIME   Creation time.

       STAT   State of the segment.  It consists of the following flags:

              a      The segment is active, meaning that it is recently
                     created and cannot be reclaimed by the garbage collector.

              d      The segment is dirty, meaning that it is in use.

              e      The segment is erroneous, meaning that it has once caused
                     an I/O error.  NILFS2 avoids allocating the segments with
                     this flag.

              p (optional)
                     The segment is protected, meaning that garbage collection
                     for the segment is prevented for some reason, for
                     instance, the protection period is not elapsed from its
                     last modified time, the segment is pinned by the file
                     system, or it is erroneous and unreclaimable, etc.  This
                     flag is displayed when -l option is specified.

              Number of in-use blocks of the segment.

       NLIVEBLOCKS (optional)
              Number and ratio of in-use blocks of the moment.  This field is
              displayed when -l option is specified.

       Koji Sato

       lssu is part of the nilfs-utils package and is available from

       nilfs(8), dumpseg(8).

nilfs-utils version 2.2            Apr 2014                            LSSU(1)