Ext3 users - Aug 2014 - extended filesystems

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.

    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.

    Why would I want to do this. to learn and I don't think I need it. Too
much overhead.

Bill

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

----- Original Message ----- 
From: "Eric Sandeen" <sandeen@redhat.com>
To: "Bill Cunningham" <billcun@suddenlink.net>;
<Ext3-users@redhat.com>
Sent: Sunday, August 17, 2014 4:47 PM
Subject: Re: extended filesystems

[snip]
> So the first thing you've learned is that it is not in fact too much
> overhead, because it's not there.  ;)
>
> -Eric
    Ok I see. Well I have used fsarchiver to save my ext4 system and the 
mkfs option to uninstall everything as an ext2 filesystem. Everything 
uncompress and is written to the block device much more quickly. I know with 
ext3 there is the journal inode which isn't present on ext2.

    Well anyway is this list for the entire ext family or just ext3?

Bill