.\"	$OpenBSD: lfs_cleanerd.8,v 1.6 1999/07/02 20:11:49 aaron Exp $
.\"
.\" Copyright (c) 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by the University of
.\"	California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"	@(#)lfs_cleanerd.8	8.2 (Berkeley) 12/11/93
.\"
.Dd December 11, 1993
.Dt LFS_CLEANERD 8
.Os
.Sh NAME
.Nm lfs_cleanerd
.Nd garbage collect a log-structured file system
.Sh SYNOPSIS
.Nm lfs_cleanerd
.Op Fl ds
.Pa node
.Sh DESCRIPTION
The
.Nm lfs_cleanerd
command starts a daemon process which garbage-collects
the log-structured file system residing at the point named by
.Ar node
in the global file system namespace.
This command is normally executed by
.Xr mount_lfs 8
when the log-structured file system is mounted.
The daemon will exit within a few minutes
of when the file system it was cleaning is unmounted.
.Pp
Garbage collection on a log-structured file system is done by scanning
the file system's segments for active, i.e. referenced, data and copying
it to new segments.
When all of the active data in a given segment has been copied to a new
segment that segment can be marked as empty, thus reclaiming the space
taken by the inactive data which was in it.
.Pp
The following options are available:
.Bl -tag -width indent
.It Fl d
Run in debug mode.
Do not become a daemon process, and print debugging information.
.It Fl s
When cleaning the file system, read data in small chunks.
.El
.Sh SEE ALSO
.Xr mount_lfs 8
.Sh HISTORY
The
.Nm lfs_cleanerd
utility first appeared in
.Bx 4.4 .