xref: /netbsd-src/libexec/lfs_cleanerd/lfs_cleanerd.8 (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
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32.\"	@(#)lfs_cleanerd.8	8.2 (Berkeley) 12/11/93
33.\"
34.Dd "December 11, 1993"
35.Dt LFS_CLEANERD 8
36.Os BSD 4.4
37.Sh NAME
38.Nm lfs_cleanerd
39.Nd garbage collect a log-structured file system
40.Sh SYNOPSIS
41.Nm lfs_cleanerd
42.Op Fl ds
43.Pa node
44.Sh DESCRIPTION
45The
46.Nm lfs_cleanerd
47command starts a daemon process which garbage-collects
48the log-structured file system residing at the point named by
49.Ar node
50in the global file system namespace.
51This command is normally executed by
52.Xr mount_lfs 8
53when the log-structured file system is mounted.
54The daemon will exit within a few minutes
55of when the file system it was cleaning is unmounted.
56.Pp
57Garbage collection on a log-structured file system is done by scanning
58the file system's segments for active, i.e. referenced, data and copying
59it to new segments.
60When all of the active data in a given segment has been copied to a new
61segment that segment can be marked as empty, thus reclaiming the space
62taken by the inactive data which was in it.
63.Pp
64The following options are available:
65.Bl -tag -width indent
66.It Fl d
67Run in debug mode.
68Do not become a daemon process, and print debugging information.
69.It Fl s
70When cleaning the file system, read data in small chunks.
71.El
72.Sh SEE ALSO
73.Xr mount_lfs 8
74.Sh HISTORY
75The
76.Nm lfs_cleanerd
77utility first appeared in 4.4BSD.
78