File: [Development] / linux-2.4-xfs / split-patches / docs-update2 (download)
Revision 1.6, Tue Aug 15 16:59:39 2006 UTC (11 years, 2 months ago) by nathans.longdrop.melbourne.sgi.com
Branch: MAIN
CVS Tags: HEAD Changes since 1.5: +0 -0
lines
Merge up to 2.4.33.
Merge of 2.4.x-xfs-melb:linux:26774a by kenmcd.
|
Index: 2.4.x-xfs/Documentation/filesystems/xfs.txt
===================================================================
--- 2.4.x-xfs.orig/Documentation/filesystems/xfs.txt 2005-06-03 16:20:58.124123454 +1000
+++ 2.4.x-xfs/Documentation/filesystems/xfs.txt 2005-12-20 14:42:49.000000000 +1100
@@ -19,32 +19,41 @@
When mounting an XFS filesystem, the following options are accepted.
- biosize=size
- Sets the preferred buffered I/O size (default size is 64K).
- "size" must be expressed as the logarithm (base2) of the
- desired I/O size.
- Valid values for this option are 14 through 16, inclusive
- (i.e. 16K, 32K, and 64K bytes). On machines with a 4K
- pagesize, 13 (8K bytes) is also a valid size.
- The preferred buffered I/O size can also be altered on an
- individual file basis using the ioctl(2) system call.
+ allocsize=size
+ Sets the buffered I/O end-of-file preallocation size when
+ doing delayed allocation writeout (default size is 64KB).
+ Valid values for this option are page size (typically 4KB)
+ through to 1GB, inclusive, in power-of-2 increments.
dmapi
Enable the DMAPI (Data Management API) event callouts.
Use with the "mtpt" option.
+ ihashsize=value
+ Sets the number of hash buckets available for hashing the
+ in-memory inodes of the specified mount point. If a value
+ of zero is used, the value selected by the default algorithm
+ will be displayed in /proc/mounts.
+
ikeep/noikeep
When inode clusters are emptied of inodes, keep them around
on the disk (ikeep) - this is the traditional XFS behaviour
and is still the default for now. Using the noikeep option,
inode clusters are returned to the free space pool.
+ 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
+ provided for backwards compatibility, but causes problems for
+ backup applications that cannot handle large inode numbers.
+
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 64K, 4 buffers for filesystems with a blocksize
- of 32K, 3 buffers for filesystems with a blocksize of 16K
+ blocksize of 64KB, 4 buffers for filesystems with a blocksize
+ of 32KB, 3 buffers for filesystems with a blocksize of 16KB
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
@@ -100,13 +109,17 @@
O_SYNC writes can be lost if the system crashes.
If timestamp updates are critical, use the osyncisosync option.
- quota/usrquota/uqnoenforce
+ uquota/usrquota/uqnoenforce/quota
User disk quota accounting enabled, and limits (optionally)
- enforced.
+ enforced. Refer to xfs_quota(8) for further details.
- grpquota/gqnoenforce
+ gquota/grpquota/gqnoenforce
Group disk quota accounting enabled and limits (optionally)
- enforced.
+ 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
@@ -122,6 +135,27 @@
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.
+
+ 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.
+
+
+
+
sysctls
=======
@@ -130,16 +164,16 @@
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: 6000)
- 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.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)
+ 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: 30000)
+ 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)
@@ -181,27 +215,29 @@
Controls whether unprivileged users can use chown to "give away"
a file to another user.
- fs.xfs.refcache_size (Min: 0 Default: 128 Max: 512)
- Controls the size of the NFS refcache, which holds references
- on files opened via NFS to improve performance. The value
- is the maximum number of files which can be in the cache at
- any one time.
-
- fs.xfs.refcache_purge (Min: 0 Default: 32 Max: 512)
- Controls the number of entries purged from the NFS refcache
- every sync interval.
-
- fs.xfs.inherit_sync (Min: 0 Default: 1 Max 1)
+ fs.xfs.inherit_sync (Min: 0 Default: 1 Max: 1)
Setting this to "1" will cause the "sync" flag set
- by the chattr(1) command on a directory to be
+ 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)
+ fs.xfs.inherit_nodump (Min: 0 Default: 1 Max: 1)
Setting this to "1" will cause the "nodump" flag set
- by the chattr(1) command on a directory to be
+ 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)
+ fs.xfs.inherit_noatime (Min: 0 Default: 1 Max: 1)
Setting this to "1" will cause the "noatime" flag set
- by the chattr(1) command on a directory to be
+ 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.