extended filesystems

[Eric Sandeen]

On 8/17/14, 2:52 PM, Bill Cunningham wrote:
>    I would like to start experiemnting with the ext filesystems. I might
> like one day to develop something. :) What files contain the ext4
> filesystem. That's what I'm running right now. I like ext 2/3/4 all of them.

fs/ext4/*.[ch]
fs/jbd2/*.[ch]

in the linux kernel source tree.

>    My fedora partition is only 20 GB in size. I don't need huge filesystem
> support which is a feature of ext4 I believe. Which feature can I remove to
> remove this feature? I know it would be done with tune2fs -O ^ and then the
> feature name.

Reading the tune2fs man page would be a start...
 
>    Why would I want to do this. to learn and I don't think I need it. Too
> much overhead.

The only feature unique to "huge filesystems" is the 64bit feature, and
it's not used by default on a small filesystem; it also cannot be added or
removed with tune2fs after the fact.

So the first thing you've learned is that it is not in fact too much
overhead, because it's not there.  ;)

-Eric