mirror of
https://github.com/torvalds/linux.git
synced 2024-11-08 21:21:47 +00:00
0acba3cd01
nodelaylog mount option is removed by commit 93b8a585. But there still be
the description about it in the xfs document. This patch removes it.
Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
260 lines
10 KiB
Plaintext
260 lines
10 KiB
Plaintext
|
|
The SGI XFS Filesystem
|
|
======================
|
|
|
|
XFS is a high performance journaling filesystem which originated
|
|
on the SGI IRIX platform. It is completely multi-threaded, can
|
|
support large files and large filesystems, extended attributes,
|
|
variable block sizes, is extent based, and makes extensive use of
|
|
Btrees (directories, extents, free space) to aid both performance
|
|
and scalability.
|
|
|
|
Refer to the documentation at http://oss.sgi.com/projects/xfs/
|
|
for further details. This implementation is on-disk compatible
|
|
with the IRIX version of XFS.
|
|
|
|
|
|
Mount Options
|
|
=============
|
|
|
|
When mounting an XFS filesystem, the following options are accepted.
|
|
|
|
allocsize=size
|
|
Sets the buffered I/O end-of-file preallocation size when
|
|
doing delayed allocation writeout (default size is 64KiB).
|
|
Valid values for this option are page size (typically 4KiB)
|
|
through to 1GiB, inclusive, in power-of-2 increments.
|
|
|
|
attr2/noattr2
|
|
The options enable/disable (default is disabled for backward
|
|
compatibility on-disk) an "opportunistic" improvement to be
|
|
made in the way inline extended attributes are stored on-disk.
|
|
When the new form is used for the first time (by setting or
|
|
removing extended attributes) the on-disk superblock feature
|
|
bit field will be updated to reflect this format being in use.
|
|
|
|
barrier
|
|
Enables the use of block layer write barriers for writes into
|
|
the journal and unwritten extent conversion. This allows for
|
|
drive level write caching to be enabled, for devices that
|
|
support write barriers.
|
|
|
|
discard
|
|
Issue command to let the block device reclaim space freed by the
|
|
filesystem. This is useful for SSD devices, thinly provisioned
|
|
LUNs and virtual machine images, but may have a performance
|
|
impact.
|
|
|
|
dmapi
|
|
Enable the DMAPI (Data Management API) event callouts.
|
|
Use with the "mtpt" option.
|
|
|
|
grpid/bsdgroups and nogrpid/sysvgroups
|
|
These options define what group ID a newly created file gets.
|
|
When grpid is set, it takes the group ID of the directory in
|
|
which it is created; otherwise (the default) it takes the fsgid
|
|
of the current process, unless the directory has the setgid bit
|
|
set, in which case it takes the gid from the parent directory,
|
|
and also gets the setgid bit set if it is a directory itself.
|
|
|
|
ihashsize=value
|
|
In memory inode hashes have been removed, so this option has
|
|
no function as of August 2007. Option is deprecated.
|
|
|
|
ikeep/noikeep
|
|
When ikeep is specified, XFS does not delete empty inode clusters
|
|
and keeps them around on disk. ikeep is the traditional XFS
|
|
behaviour. When noikeep is specified, empty inode clusters
|
|
are returned to the free space pool. The default is noikeep for
|
|
non-DMAPI mounts, while ikeep is the default when DMAPI is in use.
|
|
|
|
inode64
|
|
Indicates that XFS is allowed to create inodes at any location
|
|
in the filesystem, including those which will result in inode
|
|
numbers occupying more than 32 bits of significance. This is
|
|
the default allocation option. Applications which do not handle
|
|
inode numbers bigger than 32 bits, should use inode32 option.
|
|
|
|
inode32
|
|
Indicates that XFS is limited to create inodes at locations which
|
|
will not result in inode numbers with more than 32 bits of
|
|
significance. This is provided for backwards compatibility, since
|
|
64 bits inode numbers might cause problems for some applications
|
|
that cannot handle large inode numbers.
|
|
|
|
largeio/nolargeio
|
|
If "nolargeio" is specified, the optimal I/O reported in
|
|
st_blksize by stat(2) will be as small as possible to allow user
|
|
applications to avoid inefficient read/modify/write I/O.
|
|
If "largeio" specified, a filesystem that has a "swidth" specified
|
|
will return the "swidth" value (in bytes) in st_blksize. If the
|
|
filesystem does not have a "swidth" specified but does specify
|
|
an "allocsize" then "allocsize" (in bytes) will be returned
|
|
instead.
|
|
If neither of these two options are specified, then filesystem
|
|
will behave as if "nolargeio" was specified.
|
|
|
|
logbufs=value
|
|
Set the number of in-memory log buffers. Valid numbers range
|
|
from 2-8 inclusive.
|
|
The default value is 8 buffers for filesystems with a
|
|
blocksize of 64KiB, 4 buffers for filesystems with a blocksize
|
|
of 32KiB, 3 buffers for filesystems with a blocksize of 16KiB
|
|
and 2 buffers for all other configurations. Increasing the
|
|
number of buffers may increase performance on some workloads
|
|
at the cost of the memory used for the additional log buffers
|
|
and their associated control structures.
|
|
|
|
logbsize=value
|
|
Set the size of each in-memory log buffer.
|
|
Size may be specified in bytes, or in kilobytes with a "k" suffix.
|
|
Valid sizes for version 1 and version 2 logs are 16384 (16k) and
|
|
32768 (32k). Valid sizes for version 2 logs also include
|
|
65536 (64k), 131072 (128k) and 262144 (256k).
|
|
The default value for machines with more than 32MiB of memory
|
|
is 32768, machines with less memory use 16384 by default.
|
|
|
|
logdev=device and rtdev=device
|
|
Use an external log (metadata journal) and/or real-time device.
|
|
An XFS filesystem has up to three parts: a data section, a log
|
|
section, and a real-time section. The real-time section is
|
|
optional, and the log section can be separate from the data
|
|
section or contained within it.
|
|
|
|
mtpt=mountpoint
|
|
Use with the "dmapi" option. The value specified here will be
|
|
included in the DMAPI mount event, and should be the path of
|
|
the actual mountpoint that is used.
|
|
|
|
noalign
|
|
Data allocations will not be aligned at stripe unit boundaries.
|
|
|
|
noatime
|
|
Access timestamps are not updated when a file is read.
|
|
|
|
norecovery
|
|
The filesystem will be mounted without running log recovery.
|
|
If the filesystem was not cleanly unmounted, it is likely to
|
|
be inconsistent when mounted in "norecovery" mode.
|
|
Some files or directories may not be accessible because of this.
|
|
Filesystems mounted "norecovery" must be mounted read-only or
|
|
the mount will fail.
|
|
|
|
nouuid
|
|
Don't check for double mounted file systems using the file system uuid.
|
|
This is useful to mount LVM snapshot volumes.
|
|
|
|
uquota/usrquota/uqnoenforce/quota
|
|
User disk quota accounting enabled, and limits (optionally)
|
|
enforced. Refer to xfs_quota(8) for further details.
|
|
|
|
gquota/grpquota/gqnoenforce
|
|
Group disk quota accounting enabled and limits (optionally)
|
|
enforced. Refer to xfs_quota(8) for further details.
|
|
|
|
pquota/prjquota/pqnoenforce
|
|
Project disk quota accounting enabled and limits (optionally)
|
|
enforced. Refer to xfs_quota(8) for further details.
|
|
|
|
sunit=value and swidth=value
|
|
Used to specify the stripe unit and width for a RAID device or
|
|
a stripe volume. "value" must be specified in 512-byte block
|
|
units.
|
|
If this option is not specified and the filesystem was made on
|
|
a stripe volume or the stripe width or unit were specified for
|
|
the RAID device at mkfs time, then the mount system call will
|
|
restore the value from the superblock. For filesystems that
|
|
are made directly on RAID devices, these options can be used
|
|
to override the information in the superblock if the underlying
|
|
disk layout changes after the filesystem has been created.
|
|
The "swidth" option is required if the "sunit" option has been
|
|
specified, and must be a multiple of the "sunit" value.
|
|
|
|
swalloc
|
|
Data allocations will be rounded up to stripe width boundaries
|
|
when the current end of file is being extended and the file
|
|
size is larger than the stripe width size.
|
|
|
|
|
|
sysctls
|
|
=======
|
|
|
|
The following sysctls are available for the XFS filesystem:
|
|
|
|
fs.xfs.stats_clear (Min: 0 Default: 0 Max: 1)
|
|
Setting this to "1" clears accumulated XFS statistics
|
|
in /proc/fs/xfs/stat. It then immediately resets to "0".
|
|
|
|
fs.xfs.xfssyncd_centisecs (Min: 100 Default: 3000 Max: 720000)
|
|
The interval at which the xfssyncd thread flushes metadata
|
|
out to disk. This thread will flush log activity out, and
|
|
do some processing on unlinked inodes.
|
|
|
|
fs.xfs.xfsbufd_centisecs (Min: 50 Default: 100 Max: 3000)
|
|
The interval at which xfsbufd scans the dirty metadata buffers list.
|
|
|
|
fs.xfs.age_buffer_centisecs (Min: 100 Default: 1500 Max: 720000)
|
|
The age at which xfsbufd flushes dirty metadata buffers to disk.
|
|
|
|
fs.xfs.error_level (Min: 0 Default: 3 Max: 11)
|
|
A volume knob for error reporting when internal errors occur.
|
|
This will generate detailed messages & backtraces for filesystem
|
|
shutdowns, for example. Current threshold values are:
|
|
|
|
XFS_ERRLEVEL_OFF: 0
|
|
XFS_ERRLEVEL_LOW: 1
|
|
XFS_ERRLEVEL_HIGH: 5
|
|
|
|
fs.xfs.panic_mask (Min: 0 Default: 0 Max: 127)
|
|
Causes certain error conditions to call BUG(). Value is a bitmask;
|
|
AND together the tags which represent errors which should cause panics:
|
|
|
|
XFS_NO_PTAG 0
|
|
XFS_PTAG_IFLUSH 0x00000001
|
|
XFS_PTAG_LOGRES 0x00000002
|
|
XFS_PTAG_AILDELETE 0x00000004
|
|
XFS_PTAG_ERROR_REPORT 0x00000008
|
|
XFS_PTAG_SHUTDOWN_CORRUPT 0x00000010
|
|
XFS_PTAG_SHUTDOWN_IOERROR 0x00000020
|
|
XFS_PTAG_SHUTDOWN_LOGERROR 0x00000040
|
|
|
|
This option is intended for debugging only.
|
|
|
|
fs.xfs.irix_symlink_mode (Min: 0 Default: 0 Max: 1)
|
|
Controls whether symlinks are created with mode 0777 (default)
|
|
or whether their mode is affected by the umask (irix mode).
|
|
|
|
fs.xfs.irix_sgid_inherit (Min: 0 Default: 0 Max: 1)
|
|
Controls files created in SGID directories.
|
|
If the group ID of the new file does not match the effective group
|
|
ID or one of the supplementary group IDs of the parent dir, the
|
|
ISGID bit is cleared if the irix_sgid_inherit compatibility sysctl
|
|
is set.
|
|
|
|
fs.xfs.inherit_sync (Min: 0 Default: 1 Max: 1)
|
|
Setting this to "1" will cause the "sync" flag set
|
|
by the xfs_io(8) chattr command on a directory to be
|
|
inherited by files in that directory.
|
|
|
|
fs.xfs.inherit_nodump (Min: 0 Default: 1 Max: 1)
|
|
Setting this to "1" will cause the "nodump" flag set
|
|
by the xfs_io(8) chattr command on a directory to be
|
|
inherited by files in that directory.
|
|
|
|
fs.xfs.inherit_noatime (Min: 0 Default: 1 Max: 1)
|
|
Setting this to "1" will cause the "noatime" flag set
|
|
by the xfs_io(8) chattr command on a directory to be
|
|
inherited by files in that directory.
|
|
|
|
fs.xfs.inherit_nosymlinks (Min: 0 Default: 1 Max: 1)
|
|
Setting this to "1" will cause the "nosymlinks" flag set
|
|
by the xfs_io(8) chattr command on a directory to be
|
|
inherited by files in that directory.
|
|
|
|
fs.xfs.rotorstep (Min: 1 Default: 1 Max: 256)
|
|
In "inode32" allocation mode, this option determines how many
|
|
files the allocator attempts to allocate in the same allocation
|
|
group before moving to the next allocation group. The intent
|
|
is to control the rate at which the allocator moves between
|
|
allocation groups when allocating extents for new files.
|