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diff --git a/upstream/archlinux/man8/btrfstune.8 b/upstream/archlinux/man8/btrfstune.8 new file mode 100644 index 00000000..94cc266f --- /dev/null +++ b/upstream/archlinux/man8/btrfstune.8 @@ -0,0 +1,178 @@ +.\" Man page generated from reStructuredText. +. +. +.nr rst2man-indent-level 0 +. +.de1 rstReportMargin +\\$1 \\n[an-margin] +level \\n[rst2man-indent-level] +level margin: \\n[rst2man-indent\\n[rst2man-indent-level]] +- +\\n[rst2man-indent0] +\\n[rst2man-indent1] +\\n[rst2man-indent2] +.. +.de1 INDENT +.\" .rstReportMargin pre: +. RS \\$1 +. nr rst2man-indent\\n[rst2man-indent-level] \\n[an-margin] +. nr rst2man-indent-level +1 +.\" .rstReportMargin post: +.. +.de UNINDENT +. RE +.\" indent \\n[an-margin] +.\" old: \\n[rst2man-indent\\n[rst2man-indent-level]] +.nr rst2man-indent-level -1 +.\" new: \\n[rst2man-indent\\n[rst2man-indent-level]] +.in \\n[rst2man-indent\\n[rst2man-indent-level]]u +.. +.TH "BTRFSTUNE" "8" "Feb 14, 2024" "6.7.1" "BTRFS" +.SH NAME +btrfstune \- tune various filesystem parameters +.SH SYNOPSIS +.sp +\fBbtrfstune\fP [options] <device> [<device>...] +.SH DESCRIPTION +.sp +\fBbtrfstune\fP can be used to enable, disable, or set various filesystem +parameters. The filesystem must be unmounted. +.sp +The common use case is to enable features that were not enabled at mkfs time. +Please make sure that you have kernel support for the features. You can find a +complete list of features and kernel version of their introduction at +\fI\%Feature by version\fP page. Also, the manual page +\fI\%mkfs.btrfs(8)\fP contains more details about the features. +.sp +Some of the features could be also enabled on a mounted filesystem by other +means. Please refer to the \fIFILESYSTEM FEATURES\fP in \fI\%btrfs(5)\fP\&. +.SH OPTIONS +.INDENT 0.0 +.TP +.B \-\-convert\-to\-block\-group\-tree +(since kernel 6.1) +.sp +Convert portions of extent tree that tracks block groups to a separate +block group tree. This greatly reduces mount time. Can be also enabled +at mkfs time. +.TP +.B \-\-convert\-from\-block\-group\-tree +(since kernel 6.1) +.sp +Convert block groups tracked in standalone block group tree back to +extent tree and remove \fIblock\-group\-tree\fP feature bit from the filesystem. +.TP +.B \-\-convert\-to\-free\-space\-tree +(since kernel 4.5) +.sp +Convert to free\-space\-tree feature (v2 of space cache). +.TP +.B \-f +Allow dangerous changes, e.g. clear the seeding flag or change fsid. +Make sure that you are aware of the dangers. +.TP +.B \-m +(since kernel: 5.0) +.sp +change fsid stored as \fImetadata_uuid\fP to a randomly generated UUID, +see also \fI\-U\fP +.UNINDENT +.INDENT 0.0 +.TP +.BI \-M \ <UUID> +(since kernel: 5.0) +.sp +change fsid stored as \fImetadata_uuid\fP to a given UUID, see also \fI\-U\fP +.sp +The metadata_uuid is stored only in the superblock and is a backward +incompatible change. The fsid in metadata blocks remains unchanged and +is not overwritten, thus the whole operation is significantly faster +than \fI\-U\fP\&. +.sp +The new metadata_uuid can be used for mount by UUID and is also used to +identify devices of a multi\-device filesystem. +.TP +.B \-n +(since kernel: 3.14) +.sp +Enable no\-holes feature (more efficient representation of file holes), +enabled by mkfs feature \fIno\-holes\fP\&. +.TP +.B \-r +(since kernel: 3.7) +.sp +Enable extended inode refs (hardlink limit per file in a directory is +65536), enabled by mkfs feature \fIextref\fP\&. +.TP +.BI \-S \ <0|1> +Enable seeding on a given device. Value 1 will enable seeding, 0 will +disable it. A seeding filesystem is forced to be mounted read\-only. A +new device can be added to the filesystem and will capture all writes +keeping the seeding device intact. See also section +\fI\%SEEDING DEVICE\fP +in \fI\%btrfs(5)\fP\&. +.sp +\fBWARNING:\fP +.INDENT 7.0 +.INDENT 3.5 +Clearing the seeding flag on a device may be dangerous. If a +previously\-seeding device is changed, all filesystems that used +that device will become unmountable. Setting the seeding flag +back will not fix that. +.sp +A valid usecase is \fIseeding device as a base image\fP\&. Clear the +seeding flag, update the filesystem and make it seeding again, +provided that it\(aqs OK to throw away all filesystems built on +top of the previous base. +.UNINDENT +.UNINDENT +.TP +.B \-u +Change fsid to a randomly generated UUID or continue previous fsid +change operation in case it was interrupted. +.TP +.BI \-U \ <UUID> +Change fsid to \fIUUID\fP in all metadata blocks. +.sp +The \fIUUID\fP should be a 36 bytes string in \fBprintf(3)\fP format +\fB%08x\-%04x\-%04x\-%04x\-%012x\fP\&. +If there is a previous unfinished fsid change, it will continue only if the +\fIUUID\fP matches the unfinished one or if you use the option \fI\-u\fP\&. +.sp +All metadata blocks are rewritten, this may take some time, but the final +filesystem compatibility is unaffected, unlike \fI\-M\fP\&. +.sp +\fBWARNING:\fP +.INDENT 7.0 +.INDENT 3.5 +Cancelling or interrupting a UUID change operation will make +the filesystem temporarily unmountable. To fix it, rerun +\fBbtrfstune \-u\fP and let it complete. +.UNINDENT +.UNINDENT +.TP +.B \-x +(since kernel: 3.10) +.sp +Enable skinny metadata extent refs (more efficient representation of +extents), enabled by mkfs feature \fIskinny\-metadata\fP\&. +.sp +All newly created extents will use the new representation. To +completely switch the entire filesystem, run a full balance of the +metadata. Please refer to \fI\%btrfs\-balance(8)\fP\&. +.UNINDENT +.SH EXIT STATUS +.sp +\fBbtrfstune\fP returns 0 if no error happened, 1 otherwise. +.SH COMPATIBILITY NOTE +.sp +This deprecated tool exists for historical reasons but is still in use today. +Its functionality will be merged to the main tool, at which time \fBbtrfstune\fP +will be declared obsolete and scheduled for removal. +.SH SEE ALSO +.sp +\fI\%btrfs(5)\fP, +\fI\%btrfs\-balance(8)\fP, +\fI\%mkfs.btrfs(8)\fP +.\" Generated by docutils manpage writer. +. |