'\" t .\" Title: btrfstune .\" Author: [FIXME: author] [see http://docbook.sf.net/el/author] .\" Generator: DocBook XSL Stylesheets v1.76.1 .\" Date: 06/20/2015 .\" Manual: Btrfs Manual .\" Source: Btrfs v3.17 .\" Language: English .\" .TH "BTRFSTUNE" "8" "06/20/2015" "Btrfs v3\&.17" "Btrfs Manual" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH "NAME" btrfstune \- tune various btrfs filesystem parameters .SH "SYNOPSIS" .sp \fBbtrfstune\fR [options] \fI\fR [\fI\fR\&...] .SH "DESCRIPTION" .sp \fBbtrfstune\fR is used to tune various btrfs filesystem parameters,you can enable/disable some extended features for btrfs\&. .SH "OPTIONS" .PP \-S \fI\fR .RS 4 Updates the seeding value\&. A positive value will enable seeding, zero will disable seeding, negtive is not allowed\&. Enable seeding forces a fs readonly so that you can use it to build other filesystems\&. .RE .PP \-r .RS 4 Enable extended inode refs\&. .RE .PP \-x .RS 4 Enable skinny metadata extent refs\&. .RE .PP \-f .RS 4 Allow dangerous changes, e\&.g\&. clear the seeding flag .RE .sp When mounting the new device, btrfs will check whether the seeding flag is set when try to open seeding device\&. If the user clears the seeding flag of the seeding device, the new device will not be mountable\&. Even setting the seeding flag back will not fix this problem, because the generation will be changed at that time\&. Clear the seeding flag may damage the new filesystem\&. .SH "EXIT STATUS" .sp \fBbtrfstune\fR will return 0 if no error happened\&. If any problems happened, 1 will be returned\&. .SH "SEE ALSO" .sp \fBmkfs\&.btrfs\fR(8)