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
31 	preallocation size, which uses a set of heuristics to
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
47 	mount option is set, then that becomes the new default used
51 	will reject the ``noattr2`` mount option if it is set.
66 	gets.  When ``grpid`` is set, it takes the group ID of the
69 	``setgid`` bit set, in which case it takes the ``gid`` from the
70 	parent directory, and also gets the ``setgid`` bit set if it is
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.
128 	Enable data placement based on write life time hints provided
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
142 	stripe unit configured at **mkfs(8)** time.
148 	Use an external log (metadata journal) and/or real-time device.
150 	section, and a real-time section.  The real-time section is
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
210 	Typically the only time these mount options are necessary if
244 filesystems can now be disabled at kernel build time via Kconfig option.
245 The option will default to yes until September 2025, at which time it
259 Mounting ascii-ci filesystem    September 2030
294 	references and returns timed-out AGs back to the free stream
342 	is set.
345 	Setting this to "1" will cause the "sync" flag set
350 	Setting this to "1" will cause the "nodump" flag set
355 	Setting this to "1" will cause the "noatime" flag set
360 	Setting this to "1" will cause the "nosymlinks" flag set
365 	Setting this to "1" will cause the "nodefrag" flag set
405  -failure speed:
408 	immediately, after a defined number of retries, after a set time period,
411  -error classes:
416  -error handlers:
419 The filesystem behavior during an error can be set via ``sysfs`` files. Each
420 error handler works independently - the first condition met by an error handler
425 dependent - it may cause a shut down in the case of an unrecoverable error,
444 		- "metadata": applies metadata buffer write IO
456 	Defines the filesystem error behavior at unmount time.
458 	If set to a value of 1, XFS will override all other error configurations
460 	i.e. no retries, no retry timeout. This will always allow unmount to
463 	If set to 0, the configured retry behaviour will continue until all
469 	Note: there is no guarantee that fail_at_unmount can be set while an
485   max_retries			(Min: -1  Default: Varies  Max: INTMAX)
488 	error context (e.g. a specific metadata buffer) is reset every time
491 	Setting the value to "-1" will cause XFS to retry forever for this
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
530 time in the future.
540   xfs_iwalk-$pid  Inode scans of the entire filesystem. Currently limited to
541                   mount time quotacheck.
542   xfs-gc          Background garbage collection of disk space that have been
548 found in /sys/bus/workqueue/devices/xfs_iwalk-1111!nvme0n1/.
570 	This read-only attribute exposes the maximum number of open zones
571 	available for data placement. The value is determined at mount time and