Re: What happened to mount option "noextents"

[tytso@mit.edu]

On Sun, May 30, 2010 at 02:07:06PM +0200, Peter Hallberg wrote:
> 
> On Ubuntu 9.04 it is possible to mount an ext4 file system with the
> mount option "noextents" but on Ubuntu 10.04 it gives the error
> message: Ext4: Unrecognized mount option "noextents" in dmesg.

Both the "extents" and "noexents" mount options were removed in newer
kernels.  If you want to turn on extents, the right answer is to use
the "tune2fs -O extents" command.  The "noextents" mount option didn't
really make much sense, since it basically was either no-op (if
extents were not enabled), and was mostly useless (if extents were
enabled in the file system), since it basically meant, "create new
files without using extents".  But since the old files were still
extents-based, it didn't make the file system any more compatible with
ext3 file systems.

Basically, since we couldn't think of a good use case where the mount
options made sense, and ext4 has way too many mount options already, we
decided to remove them.

						- Ted