1.\" $NetBSD: lfs_cleanerd.8,v 1.4 1997/10/20 02:05:33 enami Exp $ 2.\" 3.\" Copyright (c) 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" from: @(#)lfs_cleanerd.8 8.2 (Berkeley) 12/11/93 35.\" 36.Dd December 11, 1993 37.Dt LFS_CLEANERD 8 38.Os BSD 4.4 39.Sh NAME 40.Nm lfs_cleanerd 41.Nd garbage collect a log-structured file system 42.Sh SYNOPSIS 43.Nm 44.Op Fl ds 45.Pa node 46.Sh DESCRIPTION 47The 48.Nm 49command starts a daemon process which garbage-collects 50the log-structured file system residing at the point named by 51.Ar node 52in the global file system namespace. 53This command is normally executed by 54.Xr mount_lfs 8 55when the log-structured file system is mounted. 56The daemon will exit within a few minutes 57of when the file system it was cleaning is unmounted. 58.Pp 59Garbage collection on a log-structured file system is done by scanning 60the file system's segments for active, i.e. referenced, data and copying 61it to new segments. 62When all of the active data in a given segment has been copied to a new 63segment that segment can be marked as empty, thus reclaiming the space 64taken by the inactive data which was in it. 65.Pp 66The following options are available: 67.Bl -tag -width indent 68.It Fl d 69Run in debug mode. 70Do not become a daemon process, and print debugging information. 71.It Fl s 72When cleaning the file system, read data in small chunks. 73.El 74.Sh SEE ALSO 75.Xr mount_lfs 8 76.Sh HISTORY 77The 78.Nm 79utility first appeared in 4.4BSD. 80