125 lines
4.5 KiB
Groff
125 lines
4.5 KiB
Groff
.\" $NetBSD: lfs_cleanerd.8,v 1.9 2001/07/13 20:30:22 perseant 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.
|
|
.\"
|
|
.\" from: @(#)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
|
|
.Op Fl bdfmqs
|
|
.Op Fl l Ar load-threshhold
|
|
.Op Fl n Ar number-of-segments
|
|
.Op Fl r Ar report-frequency
|
|
.Op Fl t Ar timeout
|
|
.Pa node
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
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 b
|
|
Use bytes written, rather than segments read, when determining how many
|
|
segments to clean at once.
|
|
.It Fl d
|
|
Run in debug mode.
|
|
Do not become a daemon process, and print debugging information. More
|
|
.Fl d
|
|
s give more detailed debugging information.
|
|
.It Fl f
|
|
Use filesystem idle time as the criterion for aggressive cleaning,
|
|
instead of system load.
|
|
.It Fl l Ar load-threshhold
|
|
Clean more aggressively when the system load is below the given
|
|
threshhold. The default threshhold is 0.2.
|
|
.It Fl m
|
|
Use mmap, rather than rereading the Ifile to update the cleaner's
|
|
knowledge of the filesystem. Do not use this option.
|
|
.It Fl n Ar number-of-segments
|
|
Clean this number of segments at a time: that is, pass this many
|
|
segments' blocks through a single call to lfs_markv, or, if
|
|
.Fl b
|
|
was also given, pass this many segments' worth of blocks through a
|
|
single call to lfs_markv.
|
|
.It Fl q
|
|
Quit after cleaning once.
|
|
.It Fl r Ar report-frequency
|
|
Give an efficiency report after every
|
|
.Ar report-frequency
|
|
times through the main loop.
|
|
.It Fl s
|
|
When cleaning the file system, send only a few blocks through lfs_markv
|
|
at a time. Don't use this option.
|
|
.It Fl t Ar timeout
|
|
Poll the filesystem every
|
|
.Ar timeout
|
|
seconds, looking for opportunities to clean. The default is 300, that
|
|
is, five minutes. Note that
|
|
.Nm
|
|
will be automatically awakened when the filesystem is active, so it is
|
|
not usually necessary to set
|
|
.Ar timeout
|
|
to a low value.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr mount_lfs 8
|
|
.Xr lfs_bmapv 2
|
|
.Xr lfs_markv 2
|
|
.Xr lfs_segwait 2
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
utility first appeared in
|
|
.Bx 4.4 .
|