aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/filesystems/ext4.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/filesystems/ext4.txt')
-rw-r--r--Documentation/filesystems/ext4.txt19
1 files changed, 15 insertions, 4 deletions
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt
index 0d5394920a31..eb154ef36c2a 100644
--- a/Documentation/filesystems/ext4.txt
+++ b/Documentation/filesystems/ext4.txt
@@ -32,9 +32,9 @@ Mailing list: linux-ext4@vger.kernel.org
32 you will need to merge your changes with the version from e2fsprogs 32 you will need to merge your changes with the version from e2fsprogs
33 1.41.x. 33 1.41.x.
34 34
35 - Create a new filesystem using the ext4dev filesystem type: 35 - Create a new filesystem using the ext4 filesystem type:
36 36
37 # mke2fs -t ext4dev /dev/hda1 37 # mke2fs -t ext4 /dev/hda1
38 38
39 Or configure an existing ext3 filesystem to support extents and set 39 Or configure an existing ext3 filesystem to support extents and set
40 the test_fs flag to indicate that it's ok for an in-development 40 the test_fs flag to indicate that it's ok for an in-development
@@ -47,13 +47,13 @@ Mailing list: linux-ext4@vger.kernel.org
47 47
48 # tune2fs -I 256 /dev/hda1 48 # tune2fs -I 256 /dev/hda1
49 49
50 (Note: we currently do not have tools to convert an ext4dev 50 (Note: we currently do not have tools to convert an ext4
51 filesystem back to ext3; so please do not do try this on production 51 filesystem back to ext3; so please do not do try this on production
52 filesystems.) 52 filesystems.)
53 53
54 - Mounting: 54 - Mounting:
55 55
56 # mount -t ext4dev /dev/hda1 /wherever 56 # mount -t ext4 /dev/hda1 /wherever
57 57
58 - When comparing performance with other filesystems, remember that 58 - When comparing performance with other filesystems, remember that
59 ext3/4 by default offers higher data integrity guarantees than most. 59 ext3/4 by default offers higher data integrity guarantees than most.
@@ -177,6 +177,11 @@ barrier=<0|1(*)> This enables/disables the use of write barriers in
177 your disks are battery-backed in one way or another, 177 your disks are battery-backed in one way or another,
178 disabling barriers may safely improve performance. 178 disabling barriers may safely improve performance.
179 179
180inode_readahead=n This tuning parameter controls the maximum
181 number of inode table blocks that ext4's inode
182 table readahead algorithm will pre-read into
183 the buffer cache. The default value is 32 blocks.
184
180orlov (*) This enables the new Orlov block allocator. It is 185orlov (*) This enables the new Orlov block allocator. It is
181 enabled by default. 186 enabled by default.
182 187
@@ -218,6 +223,11 @@ errors=remount-ro(*) Remount the filesystem read-only on an error.
218errors=continue Keep going on a filesystem error. 223errors=continue Keep going on a filesystem error.
219errors=panic Panic and halt the machine if an error occurs. 224errors=panic Panic and halt the machine if an error occurs.
220 225
226data_err=ignore(*) Just print an error message if an error occurs
227 in a file data buffer in ordered mode.
228data_err=abort Abort the journal if an error occurs in a file
229 data buffer in ordered mode.
230
221grpid Give objects the same group ID as their creator. 231grpid Give objects the same group ID as their creator.
222bsdgroups 232bsdgroups
223 233
@@ -252,6 +262,7 @@ stripe=n Number of filesystem blocks that mballoc will try
252delalloc (*) Deferring block allocation until write-out time. 262delalloc (*) Deferring block allocation until write-out time.
253nodelalloc Disable delayed allocation. Blocks are allocation 263nodelalloc Disable delayed allocation. Blocks are allocation
254 when data is copied from user to page cache. 264 when data is copied from user to page cache.
265
255Data Mode 266Data Mode
256========= 267=========
257There are 3 different data modes: 268There are 3 different data modes: