# Is delalloc option enabled for my ext4 partition?

## mrfree

Reading /usr/src/linux/Documentation/filesystems/ext4.txt I found delalloc mount option should be enabled per default, but how can I check if it's really enabled?

```
# tune2fs -l /dev/sda5

tune2fs 1.41.12 (17-May-2010)

Filesystem volume name:   <none>

Last mounted on:          /

Filesystem UUID:          1aff4ab5-7e63-4531-9c34-aca91cbb9ac2

Filesystem magic number:  0xEF53

Filesystem revision #:    1 (dynamic)

Filesystem features:      has_journal ext_attr resize_inode dir_index filetype needs_recovery extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize

Filesystem flags:         signed_directory_hash 

Default mount options:    (none)

Filesystem state:         clean

Errors behavior:          Continue

Filesystem OS type:       Linux

Inode count:              7602176

Block count:              30378907

Reserved block count:     0

Free blocks:              6366261

Free inodes:              6887709

First block:              0

Block size:               4096

Fragment size:            4096

Reserved GDT blocks:      1016

Blocks per group:         32768

Fragments per group:      32768

Inodes per group:         8192

Inode blocks per group:   512

RAID stride:              32735

Flex block group size:    16

Filesystem created:       Wed May 12 17:57:24 2010

Last mount time:          Mon Sep 13 12:45:03 2010

Last write time:          Mon Sep 13 09:13:58 2010

Mount count:              6

Maximum mount count:      31

Last checked:             Tue Sep  7 15:28:48 2010

Check interval:           15552000 (6 months)

Next check after:         Sun Mar  6 14:28:48 2011

Lifetime writes:          571 GB

Reserved blocks uid:      0 (user root)

Reserved blocks gid:      0 (group root)

First inode:              11

Inode size:             256

Required extra isize:     28

Desired extra isize:      28

Journal inode:            8

First orphan inode:       5374066

Default directory hash:   half_md4

Directory Hash Seed:      f4fd236c-774b-4f41-be2e-86c7f8e66576

Journal backup:           inode blocks

```

"Default mount options" is equal to "none" is it normal?

```
# dmesg | grep -i ext4

EXT4-fs (sda5): mounted filesystem with ordered data mode. Opts: (null)

EXT4-fs (sda5): re-mounted. Opts: (null)

EXT4-fs (sda5): re-mounted. Opts: commit=0
```

dmesg doesn't show anything special...

```
# mount

/dev/sda5 on / type ext4 (rw,noatime,commit=0)
```

nor mount

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## Etal

Considering that delayed allocation was one of the avertized features of ext4, it would be surprising if it wasn't enabled by default, even though it says it should be in the docs.

If you're really worried, you can add the delalloc option to your /etc/fstab  :Smile: 

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