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Diffstat (limited to 'upstream/fedora-rawhide/man8/xfs_fsr.8')
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diff --git a/upstream/fedora-rawhide/man8/xfs_fsr.8 b/upstream/fedora-rawhide/man8/xfs_fsr.8 new file mode 100644 index 00000000..0a162b60 --- /dev/null +++ b/upstream/fedora-rawhide/man8/xfs_fsr.8 @@ -0,0 +1,187 @@ +.TH xfs_fsr 8 +.SH NAME +xfs_fsr \- filesystem reorganizer for XFS +.SH SYNOPSIS +.nf +\f3xfs_fsr\f1 [\f3\-vdg\f1] \c +[\f3\-t\f1 seconds] [\f3\-p\f1 passes] [\f3\-f\f1 leftoff] [\f3\-m\f1 mtab] +\f3xfs_fsr\f1 [\f3\-vdg\f1] \c +[xfsdev | file] ... +.br +.B xfs_fsr \-V +.fi +.SH DESCRIPTION +.I xfs_fsr +is applicable only to XFS filesystems. +.PP +.I xfs_fsr +improves the organization of mounted filesystems. +The reorganization algorithm operates on one file at a time, +compacting or otherwise improving the layout of +the file extents (contiguous blocks of file data). +.PP +The following options are accepted by +.IR xfs_fsr . +The +.BR \-m , +.BR \-t , +and +.B \-f +options have no meaning if any filesystems +or files are specified on the command line. +.TP 13 +.BI \-m " mtab" +Use this file for the list of filesystems to reorganize. +The default is to use +.IR /etc/mtab . +.TP +.BI \-t " seconds" +How long to reorganize. +The default is 7200 seconds (2 hours). +.TP +.BI \-p " passes" +Number of passes before terminating global re-org. +The default is 10 passes. +.TP +.BI \-f " leftoff" +Use this file instead of +.I /var/tmp/.fsrlast +to read the state of where to start and as the file +to store the state of where reorganization left off. +.TP +.B \-v +Verbose. +Print cryptic information about +each file being reorganized. +.TP +.B \-d +Debug. Print even more cryptic information. +.TP +.B \-g +Print to syslog (default if stdout not a tty). +.TP +.B \-V +Prints the version number and exits. + +.PP +When invoked with no arguments +.I xfs_fsr +reorganizes all regular files in all mounted filesystems. +.I xfs_fsr +makes many cycles over +.I /etc/mtab +each time making a single pass over each XFS filesystem. +Each pass goes through and selects files +that have the largest number of extents. It attempts +to defragment the top 10% of these files on each pass. +.PP +It runs for up to two hours after which it records the filesystem +where it left off, so it can start there the next time. +This information is stored in the file +.I /var/tmp/.fsrlast_xfs. +If the information found here +is somehow inconsistent or out of date +it is ignored +and reorganization starts at the beginning of the first +filesystem found in +.IR /etc/mtab . +.PP +.I xfs_fsr +can be called with one or more arguments +naming filesystems (block device name), +and files to reorganize. +In this mode +.I xfs_fsr +does not read or write +.I /var/tmp/.fsrlast_xfs +nor does it run for a fixed time interval. +It makes one pass through each specified regular file and +all regular files in each specified filesystem. +A command line name referring to a symbolic link +(except to a file system device), +FIFO, or UNIX domain socket +generates a warning message, but is otherwise ignored. +While traversing the filesystem these types +of files are silently skipped. +.SH FILES +.PD 0 +.TP 21 +/etc/mtab +contains default list of filesystems to reorganize. +.TP 21 +/var/tmp/.fsrlast_xfs +records the state where reorganization left off. +.PD +.SH "SEE ALSO" +xfs_fsr(8), +mkfs.xfs(8), +xfs_ncheck(8), +xfs(5). +.SH "NOTES" +.I xfs_fsr +improves the layout of extents for each file by copying the entire +file to a temporary location and then interchanging the data extents +of the target and temporary files in an atomic manner. +This method requires that enough free disk space be available to copy +any given file and that the space be less fragmented than the original +file. +It also requires the owner of the file to have enough remaining +filespace quota to do the copy on systems running quotas. +.I xfs_fsr +generates a warning message if space is not sufficient to improve +the target file. +.PP +A temporary file used in improving a file given on the command line +is created in the same parent directory of the target file and +is prefixed by the string '\f3.fsr\f1'. +The temporary files used in improving an entire XFS device are stored +in a directory at the root of the target device and use the same +naming scheme. +The temporary files are unlinked upon creation so data will not be +readable by any other process. +.PP +.I xfs_fsr +does not operate on files that are currently mapped in memory. +A 'file busy' error can be seen for these files if the verbose +flag (\f3-v\f1) is set. +.PP +Files marked as no\-defrag will be skipped. The +.IR xfs_io (8) +chattr command with the f attribute can be used to set or clear +this flag. Files and directories created in a directory with the +no\-defrag flag will inherit the attribute. +.PP +An entry in +.I /etc/mtab +or the file specified using the +.B \-m +option must have the +.B rw +option specified for read and write access. +If this option is not present, then +.I xfs_fsr +skips the +filesystem described by that line. +See the +.IR fstab (5) +reference page for +more details. +.PP +In general we do not foresee the need to run +.I xfs_fsr +on system partitions such as +.IR / , +.I /boot +and +.I /usr +as in general these will not suffer from fragmentation. +There are also issues with defragmenting files +.IR lilo (8) +uses to boot your system. It is recommended that these files +should be flagged as no\-defrag with the +.IR xfs_io (8) +chattr command. Should these files be moved by +.I xfs_fsr +then you must rerun +.I lilo +before you reboot or you may have an unbootable system. |