Date: Sun, 3 Jan 2010 15:20:52 +0000 (UTC) From: Edward Tomasz Napierala <trasz@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r201432 - in head/sbin/geom: class/cache core Message-ID: <201001031520.o03FKqCN069221@svn.freebsd.org>
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Author: trasz Date: Sun Jan 3 15:20:52 2010 New Revision: 201432 URL: http://svn.freebsd.org/changeset/base/201432 Log: Add manual page for gcache(8). Added: head/sbin/geom/class/cache/gcache.8 (contents, props changed) Modified: head/sbin/geom/class/cache/Makefile head/sbin/geom/core/geom.8 Modified: head/sbin/geom/class/cache/Makefile ============================================================================== --- head/sbin/geom/class/cache/Makefile Sun Jan 3 15:01:38 2010 (r201431) +++ head/sbin/geom/class/cache/Makefile Sun Jan 3 15:20:52 2010 (r201432) @@ -3,6 +3,5 @@ .PATH: ${.CURDIR}/../../misc CLASS= cache -NO_MAN= # notyet .include <bsd.lib.mk> Added: head/sbin/geom/class/cache/gcache.8 ============================================================================== --- /dev/null 00:00:00 1970 (empty, because file is newly added) +++ head/sbin/geom/class/cache/gcache.8 Sun Jan 3 15:20:52 2010 (r201432) @@ -0,0 +1,192 @@ +.\"- +.\" Copyright (c) 2010 Edward Tomasz Napierala +.\" 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. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR OR THE VOICES IN HIS HEAD 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. +.\" +.\" $FreeBSD$ +.\" +.Dd January 3, 2010 +.Dt GCACHE 8 +.Os +.Sh NAME +.Nm gcache +.Nd "control utility for CACHE GEOM class" +.Sh SYNOPSIS +.Nm +.Cm create +.Op Fl v +.Op Fl b Ar blocksize +.Op Fl s Ar size +.Ar name +.Ar prov +.Nm +.Cm configure +.Op Fl v +.Op Fl b Ar blocksize +.Op Fl s Ar size +.Ar name +.Nm +.Cm destroy +.Op Fl fv +.Ar name +.Nm +.Cm label +.Op Fl v +.Op Fl b Ar blocksize +.Op Fl s Ar size +.Ar name +.Ar prov +.Nm +.Cm stop +.Op Fl fv +.Ar name ... +.Nm +.Cm clear +.Op Fl v +.Ar prov ... +.Nm +.Cm dump +.Ar prov ... +.Nm +.Cm list +.Nm +.Cm status +.Op Fl s Ar name +.Nm +.Cm load +.Op Fl v +.Nm +.Cm unload +.Op Fl v +.Sh DESCRIPTION +The +.Nm +utility is used to control GEOM cache, which can +speed up read performance by sending fixed size +read requests to its consumer. It has been developed to address +the problem of a horrible read performance of a 64k blocksize FS +residing on a RAID3 array with 8 data components, where a single +disk component would only get 8k read requests, thus effectively +killing disk performance under high load. +.Pp +Caching can be configured using two different methods: +.Dq manual +or +.Dq automatic . +When using the +.Dq manual +method, no metadata are stored on the devices, so the cached +device has to be configured by hand every time it is needed. +The +.Dq automatic +method uses on-disk metadata to detect devices. +Once devices are labeled, they will be automatically detected and +configured. +.Pp +The first argument to +.Nm +indicates an action to be performed: +.Bl -tag -width ".Cm destroy" +.It Cm create +Cache the given devices with specified +.Ar name . +This is the +.Dq manual +method. +The kernel module +.Pa geom_cache.ko +will be loaded if it is not loaded already. +.It Cm label +Cache the given devices with the specified +.Ar name . +This is the +.Dq automatic +method, where metadata are stored in every device's last sector. +The kernel module +.Pa geom_cache.ko +will be loaded if it is not loaded already. +.It Cm stop +Turn off existing cache device by its +.Ar name . +This command does not touch on-disk metadata! +.It Cm destroy +Same as +.Cm stop . +.It Cm clear +Clear metadata on the given devices. +.It Cm dump +Dump metadata stored on the given devices. +.It Cm list +See +.Xr geom 8 . +.It Cm status +See +.Xr geom 8 . +.It Cm load +See +.Xr geom 8 . +.It Cm unload +See +.Xr geom 8 . +.El +.Pp +Additional options: +.Bl -tag -width indent +.It Fl f +Force the removal of the specified cache device. +.It Fl v +Be more verbose. +.El +.Sh SYSCTL VARIABLES +The following +.Xr sysctl 8 +variables can be used to control the behavior of the +.Nm CACHE +GEOM class. +The default value is shown next to each variable. +.Bl -tag -width indent +.It Va kern.geom.cache.used_hi : No 20 +.It Va kern.geom.cache.used_lo : No 5 +.It Va kern.geom.cache.idletime : No 5 +.It Va kern.geom.cache.timeout : No 10 +.It Va kern.geom.cache.enable : No 1 +.It Va kern.geom.cache.debug : No 0 +Debug level of the +.Nm CACHE +GEOM class. +This can be set to a number between 0 and 3 inclusive. +If set to 0 minimal debug information is printed, and if set to 3 the +maximum amount of debug information is printed. +.El +.Sh EXIT STATUS +Exit status is 0 on success, and 1 if the command fails. +.Sh SEE ALSO +.Xr geom 4 , +.Xr geom 8 +.Sh HISTORY +The +.Nm +utility appeared in +.Fx 7.0 . +.Sh AUTHORS +.An Ruslan Ermilov Aq ru@FreeBSD.org Modified: head/sbin/geom/core/geom.8 ============================================================================== --- head/sbin/geom/core/geom.8 Sun Jan 3 15:01:38 2010 (r201431) +++ head/sbin/geom/core/geom.8 Sun Jan 3 15:20:52 2010 (r201432) @@ -166,7 +166,7 @@ geom md unload .Sh SEE ALSO .Xr libgeom 3 , .Xr geom 4 , -.\" .Xr gcache 8 , +.Xr gcache 8 , .Xr gconcat 8 , .Xr geli 8 , .Xr gjournal 8 ,
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