svn commit: r341505 - head/share/man/man5

[Pedro Giffuni]

On 05/12/2018 12:41, Conrad Meyer wrote:
> On Wed, Dec 5, 2018 at 7:24 AM Pedro Giffuni<pfg at freebsd.org>  wrote:
>> On 12/5/18 12:06 AM, Kubilay Kocak wrote:
>>> Can we remove '2' from the module/man/etc name if (since) it supports
>>> multiple extXfs versions? Is there anything serious preventing it?
>> You can currently create plain ext2 filesystems on FreeBSD and add
>> ext3/4 features on top and it will work just fine. The distinction on
>> linux about ext2/3/4 is rather accidental: they didn't master Version
>> Control in time to branch instead of forking the implementation a couple
>> of times. It also seems like ext3 disappeared.
> The Linux model is that the current incarnation of the ext2/3/4 driver
> is named "ext4," and that's what Linux users expect.  You can mount
> any ext2/3/4 filesystem with the Linux ext4 driver.  For ext4, it was
> a result of wanting to keep ext3 stable while developing ext4 in-tree.
> (For a while, it was called "ext4dev").  ext4 is long-since stabilized
> and ext3 became fully redundant with ext4, so I guess they dropped it.

 From a linux user/marketing perspective you are right.

Are we sure there will never be an ext5fs? I would hate to start moving 
a filesystem in the tree every time a new release comes out.

> I think we should just follow that convention and rename ext2fs to
> ext4fs.   We can mention support for the less-used ancient ext2/3 in a
> COMPATIBILITY section or something, if we don't already, but ext4 has
> been the go-to basic Linux filesystem for a decade.  (Seriously:  "On
> 11 October 2008, the patches that mark ext4 as stable code were merged
> in the Linux 2.6.28.")  If we support ext4, call it ext4.

We do support enough of ext4 that we could call it ext4 ...

OTOH, the implementation is pretty much UFS1 plus ext2/3/4 extensions.

I like it as it is because people looking at the code will find out 
exactly where it all comes from: we are currently doing no effort keep 
up to date with what ext4 does and we are focusing on compatibility.  
For now I think adding a link in the documentation as others have 
suggested is enough.

> My 2¢,
> Conrad

Thanks! All feedback is appreciated.

Pedro.