Documentation/admin-guide/xfs.rst

1 .. SPDX-License-Identifier: GPL-2.0
8 on the SGI IRIX platform.  It is completely multi-threaded, can
15 for further details.  This implementation is on-disk compatible
25 	Sets the buffered I/O end-of-file preallocation size when
28 	through to 1GiB, inclusive, in power-of-2 increments.
30 	The default behaviour is for dynamic end-of-file
40 	on-disk.  When the new form is used for the first time when
42 	attributes) the on-disk superblock feature bit field will be
45 	The default behaviour is determined by the on-disk feature
48 	by the filesystem.
55 	device reclaim space freed by the filesystem.  This is
65 	These options define what group ID a newly created file
103 	``st_blksize`` by **stat(2)** will be as small as possible to allow
116 	Set the number of in-memory log buffers.  Valid numbers
117 	range from 2-8 inclusive.
129 	by the user. This turns on co-allocation of data of similar
136 	Set the size of each in-memory log buffer.  The size may be
145 	default value for version 2 logs is MAX(32768, log_sunit).
148 	Use an external log (metadata journal) and/or real-time device.
150 	section, and a real-time section.  The real-time section is
155 	Specify the max number of zones to keep open for writing on a
160 	by the capabilities and the size of the zoned rt device.
165 	with non-zero data alignment parameters (``sunit``, ``swidth``) by
173 	Filesystems mounted ``norecovery`` must be mounted read-only or
180 	read-only snapshots.
200 	or a stripe volume.  "value" must be specified in 512-byte
202 	that were created with non-zero data alignment parameters.
207 	increasing it by a power-of-2 multiple. Valid ``swidth`` values
232 The V4 filesystem format lacks certain features that are supported by
236 by backing up their files, reformatting, and restoring from the backup.
238 Administrators and users can detect a V4 filesystem by running xfs_info
259 Mounting ascii-ci filesystem    September 2030
284   fs.xfs.stats_clear		(Min: 0  Default: 0  Max: 1)
288   fs.xfs.xfssyncd_centisecs	(Min: 100  Default: 3000  Max: 720000)
292   fs.xfs.filestream_centisecs	(Min: 1  Default: 3000  Max: 360000)
294 	references and returns timed-out AGs back to the free stream
298 	(Units: seconds   Min: 1  Default: 300  Max: 86400)
307   fs.xfs.error_level		(Min: 0  Default: 3  Max: 11)
316   fs.xfs.panic_mask		(Min: 0  Default: 0  Max: 511)
333   fs.xfs.irix_symlink_mode	(Min: 0  Default: 0  Max: 1)
335 	or whether their mode is affected by the umask (irix mode).
337   fs.xfs.irix_sgid_inherit	(Min: 0  Default: 0  Max: 1)
344   fs.xfs.inherit_sync		(Min: 0  Default: 1  Max: 1)
346 	by the **xfs_io(8)** chattr command on a directory to be
347 	inherited by files in that directory.
349   fs.xfs.inherit_nodump		(Min: 0  Default: 1  Max: 1)
351 	by the **xfs_io(8)** chattr command on a directory to be
352 	inherited by files in that directory.
354   fs.xfs.inherit_noatime	(Min: 0  Default: 1  Max: 1)
356 	by the **xfs_io(8)** chattr command on a directory to be
357 	inherited by files in that directory.
359   fs.xfs.inherit_nosymlinks	(Min: 0  Default: 1  Max: 1)
361 	by the **xfs_io(8)** chattr command on a directory to be
362 	inherited by files in that directory.
364   fs.xfs.inherit_nodefrag	(Min: 0  Default: 1  Max: 1)
366 	by the **xfs_io(8)** chattr command on a directory to be
367 	inherited by files in that directory.
369   fs.xfs.rotorstep		(Min: 1  Default: 1  Max: 256)
405  -failure speed:
411  -error classes:
416  -error handlers:
420 error handler works independently - the first condition met by an error handler
424 The action taken by the filesystem when the error is propagated is context
425 dependent - it may cause a shut down in the case of an unrecoverable error,
444 		- "metadata": applies metadata buffer write IO
455   fail_at_unmount		(Min:  0  Default:  1  Max: 1)
471 	removed by the unmounting filesystem before a "retry forever" error
476 Each filesystem has specific error class handlers that define the error
485   max_retries			(Min: -1  Default: Varies  Max: INTMAX)
491 	Setting the value to "-1" will cause XFS to retry forever for this
497 	Setting the value to "N" (where 0 < N < Max) will make XFS retry the
500   retry_timeout_seconds		(Min:  -1  Default:  Varies  Max: 1 day)
501 	Define the amount of time (in seconds) that the filesystem is
505 	Setting the value to "-1" will allow XFS to retry forever for this
511 	Setting the value to "N" (where 0 < N < Max) will allow XFS to retry the
516 "metadata/ENODEV" are "0" rather than "-1" so that this error handler defaults
532 The control knobs for a filesystem's workqueues are organized by task at hand
540   xfs_iwalk-$pid  Inode scans of the entire filesystem. Currently limited to
542   xfs-gc          Background garbage collection of disk space that have been
548 found in /sys/bus/workqueue/devices/xfs_iwalk-1111!nvme0n1/.
569   max_open_zones		(Min:  1  Default:  Varies  Max:  UINTMAX)
570 	This read-only attribute exposes the maximum number of open zones
572 	is limited by the capabilities of the backing zoned device, file system
575   zonegc_low_space		(Min:  0  Default:  0  Max:  100)
576 	Define a percentage for how much of the unused space that GC should keep
578 	occupied by unused blocks, creating a larger buffer against write