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authorLinus Torvalds <torvalds@g5.osdl.org>2005-11-03 19:25:58 -0500
committerLinus Torvalds <torvalds@g5.osdl.org>2005-11-03 19:25:58 -0500
commit0f3278d14f0255e4cd9e07ccefc33ff12d8bb59c (patch)
tree9bbb209cab841f700162a96e158dfa3ecd361f46 /Documentation
parent06024f217d607369f0ee0071034ebb03071d5fb2 (diff)
parent15c84a470116b2a3b58a7353a6cf711c29a91854 (diff)
Merge git://oss.sgi.com:8090/oss/git/xfs-2.6
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/filesystems/xfs.txt142
1 files changed, 108 insertions, 34 deletions
diff --git a/Documentation/filesystems/xfs.txt b/Documentation/filesystems/xfs.txt
index c7d5d0c7067d..74aeb142ae5f 100644
--- a/Documentation/filesystems/xfs.txt
+++ b/Documentation/filesystems/xfs.txt
@@ -19,15 +19,43 @@ Mount Options
19 19
20When mounting an XFS filesystem, the following options are accepted. 20When mounting an XFS filesystem, the following options are accepted.
21 21
22 biosize=size 22 allocsize=size
23 Sets the preferred buffered I/O size (default size is 64K). 23 Sets the buffered I/O end-of-file preallocation size when
24 "size" must be expressed as the logarithm (base2) of the 24 doing delayed allocation writeout (default size is 64KiB).
25 desired I/O size. 25 Valid values for this option are page size (typically 4KiB)
26 Valid values for this option are 14 through 16, inclusive 26 through to 1GiB, inclusive, in power-of-2 increments.
27 (i.e. 16K, 32K, and 64K bytes). On machines with a 4K 27
28 pagesize, 13 (8K bytes) is also a valid size. 28 attr2/noattr2
29 The preferred buffered I/O size can also be altered on an 29 The options enable/disable (default is disabled for backward
30 individual file basis using the ioctl(2) system call. 30 compatibility on-disk) an "opportunistic" improvement to be
31 made in the way inline extended attributes are stored on-disk.
32 When the new form is used for the first time (by setting or
33 removing extended attributes) the on-disk superblock feature
34 bit field will be updated to reflect this format being in use.
35
36 barrier
37 Enables the use of block layer write barriers for writes into
38 the journal and unwritten extent conversion. This allows for
39 drive level write caching to be enabled, for devices that
40 support write barriers.
41
42 dmapi
43 Enable the DMAPI (Data Management API) event callouts.
44 Use with the "mtpt" option.
45
46 grpid/bsdgroups and nogrpid/sysvgroups
47 These options define what group ID a newly created file gets.
48 When grpid is set, it takes the group ID of the directory in
49 which it is created; otherwise (the default) it takes the fsgid
50 of the current process, unless the directory has the setgid bit
51 set, in which case it takes the gid from the parent directory,
52 and also gets the setgid bit set if it is a directory itself.
53
54 ihashsize=value
55 Sets the number of hash buckets available for hashing the
56 in-memory inodes of the specified mount point. If a value
57 of zero is used, the value selected by the default algorithm
58 will be displayed in /proc/mounts.
31 59
32 ikeep/noikeep 60 ikeep/noikeep
33 When inode clusters are emptied of inodes, keep them around 61 When inode clusters are emptied of inodes, keep them around
@@ -35,12 +63,31 @@ When mounting an XFS filesystem, the following options are accepted.
35 and is still the default for now. Using the noikeep option, 63 and is still the default for now. Using the noikeep option,
36 inode clusters are returned to the free space pool. 64 inode clusters are returned to the free space pool.
37 65
66 inode64
67 Indicates that XFS is allowed to create inodes at any location
68 in the filesystem, including those which will result in inode
69 numbers occupying more than 32 bits of significance. This is
70 provided for backwards compatibility, but causes problems for
71 backup applications that cannot handle large inode numbers.
72
73 largeio/nolargeio
74 If "nolargeio" is specified, the optimal I/O reported in
75 st_blksize by stat(2) will be as small as possible to allow user
76 applications to avoid inefficient read/modify/write I/O.
77 If "largeio" specified, a filesystem that has a "swidth" specified
78 will return the "swidth" value (in bytes) in st_blksize. If the
79 filesystem does not have a "swidth" specified but does specify
80 an "allocsize" then "allocsize" (in bytes) will be returned
81 instead.
82 If neither of these two options are specified, then filesystem
83 will behave as if "nolargeio" was specified.
84
38 logbufs=value 85 logbufs=value
39 Set the number of in-memory log buffers. Valid numbers range 86 Set the number of in-memory log buffers. Valid numbers range
40 from 2-8 inclusive. 87 from 2-8 inclusive.
41 The default value is 8 buffers for filesystems with a 88 The default value is 8 buffers for filesystems with a
42 blocksize of 64K, 4 buffers for filesystems with a blocksize 89 blocksize of 64KiB, 4 buffers for filesystems with a blocksize
43 of 32K, 3 buffers for filesystems with a blocksize of 16K 90 of 32KiB, 3 buffers for filesystems with a blocksize of 16KiB
44 and 2 buffers for all other configurations. Increasing the 91 and 2 buffers for all other configurations. Increasing the
45 number of buffers may increase performance on some workloads 92 number of buffers may increase performance on some workloads
46 at the cost of the memory used for the additional log buffers 93 at the cost of the memory used for the additional log buffers
@@ -49,10 +96,10 @@ When mounting an XFS filesystem, the following options are accepted.
49 logbsize=value 96 logbsize=value
50 Set the size of each in-memory log buffer. 97 Set the size of each in-memory log buffer.
51 Size may be specified in bytes, or in kilobytes with a "k" suffix. 98 Size may be specified in bytes, or in kilobytes with a "k" suffix.
52 Valid sizes for version 1 and version 2 logs are 16384 (16k) and 99 Valid sizes for version 1 and version 2 logs are 16384 (16k) and
53 32768 (32k). Valid sizes for version 2 logs also include 100 32768 (32k). Valid sizes for version 2 logs also include
54 65536 (64k), 131072 (128k) and 262144 (256k). 101 65536 (64k), 131072 (128k) and 262144 (256k).
55 The default value for machines with more than 32MB of memory 102 The default value for machines with more than 32MiB of memory
56 is 32768, machines with less memory use 16384 by default. 103 is 32768, machines with less memory use 16384 by default.
57 104
58 logdev=device and rtdev=device 105 logdev=device and rtdev=device
@@ -62,6 +109,11 @@ When mounting an XFS filesystem, the following options are accepted.
62 optional, and the log section can be separate from the data 109 optional, and the log section can be separate from the data
63 section or contained within it. 110 section or contained within it.
64 111
112 mtpt=mountpoint
113 Use with the "dmapi" option. The value specified here will be
114 included in the DMAPI mount event, and should be the path of
115 the actual mountpoint that is used.
116
65 noalign 117 noalign
66 Data allocations will not be aligned at stripe unit boundaries. 118 Data allocations will not be aligned at stripe unit boundaries.
67 119
@@ -91,13 +143,17 @@ When mounting an XFS filesystem, the following options are accepted.
91 O_SYNC writes can be lost if the system crashes. 143 O_SYNC writes can be lost if the system crashes.
92 If timestamp updates are critical, use the osyncisosync option. 144 If timestamp updates are critical, use the osyncisosync option.
93 145
94 quota/usrquota/uqnoenforce 146 uquota/usrquota/uqnoenforce/quota
95 User disk quota accounting enabled, and limits (optionally) 147 User disk quota accounting enabled, and limits (optionally)
96 enforced. 148 enforced. Refer to xfs_quota(8) for further details.
97 149
98 grpquota/gqnoenforce 150 gquota/grpquota/gqnoenforce
99 Group disk quota accounting enabled and limits (optionally) 151 Group disk quota accounting enabled and limits (optionally)
100 enforced. 152 enforced. Refer to xfs_quota(8) for further details.
153
154 pquota/prjquota/pqnoenforce
155 Project disk quota accounting enabled and limits (optionally)
156 enforced. Refer to xfs_quota(8) for further details.
101 157
102 sunit=value and swidth=value 158 sunit=value and swidth=value
103 Used to specify the stripe unit and width for a RAID device or 159 Used to specify the stripe unit and width for a RAID device or
@@ -113,15 +169,21 @@ When mounting an XFS filesystem, the following options are accepted.
113 The "swidth" option is required if the "sunit" option has been 169 The "swidth" option is required if the "sunit" option has been
114 specified, and must be a multiple of the "sunit" value. 170 specified, and must be a multiple of the "sunit" value.
115 171
172 swalloc
173 Data allocations will be rounded up to stripe width boundaries
174 when the current end of file is being extended and the file
175 size is larger than the stripe width size.
176
177
116sysctls 178sysctls
117======= 179=======
118 180
119The following sysctls are available for the XFS filesystem: 181The following sysctls are available for the XFS filesystem:
120 182
121 fs.xfs.stats_clear (Min: 0 Default: 0 Max: 1) 183 fs.xfs.stats_clear (Min: 0 Default: 0 Max: 1)
122 Setting this to "1" clears accumulated XFS statistics 184 Setting this to "1" clears accumulated XFS statistics
123 in /proc/fs/xfs/stat. It then immediately resets to "0". 185 in /proc/fs/xfs/stat. It then immediately resets to "0".
124 186
125 fs.xfs.xfssyncd_centisecs (Min: 100 Default: 3000 Max: 720000) 187 fs.xfs.xfssyncd_centisecs (Min: 100 Default: 3000 Max: 720000)
126 The interval at which the xfssyncd thread flushes metadata 188 The interval at which the xfssyncd thread flushes metadata
127 out to disk. This thread will flush log activity out, and 189 out to disk. This thread will flush log activity out, and
@@ -143,9 +205,9 @@ The following sysctls are available for the XFS filesystem:
143 XFS_ERRLEVEL_HIGH: 5 205 XFS_ERRLEVEL_HIGH: 5
144 206
145 fs.xfs.panic_mask (Min: 0 Default: 0 Max: 127) 207 fs.xfs.panic_mask (Min: 0 Default: 0 Max: 127)
146 Causes certain error conditions to call BUG(). Value is a bitmask; 208 Causes certain error conditions to call BUG(). Value is a bitmask;
147 AND together the tags which represent errors which should cause panics: 209 AND together the tags which represent errors which should cause panics:
148 210
149 XFS_NO_PTAG 0 211 XFS_NO_PTAG 0
150 XFS_PTAG_IFLUSH 0x00000001 212 XFS_PTAG_IFLUSH 0x00000001
151 XFS_PTAG_LOGRES 0x00000002 213 XFS_PTAG_LOGRES 0x00000002
@@ -155,7 +217,7 @@ The following sysctls are available for the XFS filesystem:
155 XFS_PTAG_SHUTDOWN_IOERROR 0x00000020 217 XFS_PTAG_SHUTDOWN_IOERROR 0x00000020
156 XFS_PTAG_SHUTDOWN_LOGERROR 0x00000040 218 XFS_PTAG_SHUTDOWN_LOGERROR 0x00000040
157 219
158 This option is intended for debugging only. 220 This option is intended for debugging only.
159 221
160 fs.xfs.irix_symlink_mode (Min: 0 Default: 0 Max: 1) 222 fs.xfs.irix_symlink_mode (Min: 0 Default: 0 Max: 1)
161 Controls whether symlinks are created with mode 0777 (default) 223 Controls whether symlinks are created with mode 0777 (default)
@@ -164,25 +226,37 @@ The following sysctls are available for the XFS filesystem:
164 fs.xfs.irix_sgid_inherit (Min: 0 Default: 0 Max: 1) 226 fs.xfs.irix_sgid_inherit (Min: 0 Default: 0 Max: 1)
165 Controls files created in SGID directories. 227 Controls files created in SGID directories.
166 If the group ID of the new file does not match the effective group 228 If the group ID of the new file does not match the effective group
167 ID or one of the supplementary group IDs of the parent dir, the 229 ID or one of the supplementary group IDs of the parent dir, the
168 ISGID bit is cleared if the irix_sgid_inherit compatibility sysctl 230 ISGID bit is cleared if the irix_sgid_inherit compatibility sysctl
169 is set. 231 is set.
170 232
171 fs.xfs.restrict_chown (Min: 0 Default: 1 Max: 1) 233 fs.xfs.restrict_chown (Min: 0 Default: 1 Max: 1)
172 Controls whether unprivileged users can use chown to "give away" 234 Controls whether unprivileged users can use chown to "give away"
173 a file to another user. 235 a file to another user.
174 236
175 fs.xfs.inherit_sync (Min: 0 Default: 1 Max 1) 237 fs.xfs.inherit_sync (Min: 0 Default: 1 Max: 1)
176 Setting this to "1" will cause the "sync" flag set 238 Setting this to "1" will cause the "sync" flag set
177 by the chattr(1) command on a directory to be 239 by the xfs_io(8) chattr command on a directory to be
178 inherited by files in that directory. 240 inherited by files in that directory.
179 241
180 fs.xfs.inherit_nodump (Min: 0 Default: 1 Max 1) 242 fs.xfs.inherit_nodump (Min: 0 Default: 1 Max: 1)
181 Setting this to "1" will cause the "nodump" flag set 243 Setting this to "1" will cause the "nodump" flag set
182 by the chattr(1) command on a directory to be 244 by the xfs_io(8) chattr command on a directory to be
183 inherited by files in that directory. 245 inherited by files in that directory.
184 246
185 fs.xfs.inherit_noatime (Min: 0 Default: 1 Max 1) 247 fs.xfs.inherit_noatime (Min: 0 Default: 1 Max: 1)
186 Setting this to "1" will cause the "noatime" flag set 248 Setting this to "1" will cause the "noatime" flag set
187 by the chattr(1) command on a directory to be 249 by the xfs_io(8) chattr command on a directory to be
188 inherited by files in that directory. 250 inherited by files in that directory.
251
252 fs.xfs.inherit_nosymlinks (Min: 0 Default: 1 Max: 1)
253 Setting this to "1" will cause the "nosymlinks" flag set
254 by the xfs_io(8) chattr command on a directory to be
255 inherited by files in that directory.
256
257 fs.xfs.rotorstep (Min: 1 Default: 1 Max: 256)
258 In "inode32" allocation mode, this option determines how many
259 files the allocator attempts to allocate in the same allocation
260 group before moving to the next allocation group. The intent
261 is to control the rate at which the allocator moves between
262 allocation groups when allocating extents for new files.