Does `-O bigalloc` still conflict with `delalloc`?

Does `-O bigalloc` still conflict with `delalloc`?

[Kiselev, Oleg]

The `ext4(5)` man page, contained in the most recent e2fsprogs still says:

	Warning: The bigalloc feature is still under development, and may not be fully  supported
              with your kernel or may have various bugs.  Please see the web page http://ext4.wiki.ker‐
              nel.org/index.php/Bigalloc for details.  May clash with delayed allocation (see  nodelal‐
              loc mount option).

Is a bad interaction with `delalloc` still an issue and should we be using the `nodelalloc` option? 

Re: Does `-O bigalloc` still conflict with `delalloc`?

[Theodore Ts'o]

On Sat, May 21, 2022 at 02:39:00AM +0000, Kiselev, Oleg wrote:
> The `ext4(5)` man page, contained in the most recent e2fsprogs still says:
> 
> 	Warning: The bigalloc feature is still under development, and may not be fully  supported
>               with your kernel or may have various bugs.  Please see the web page http://ext4.wiki.ker‐
>               nel.org/index.php/Bigalloc for details.  May clash with delayed allocation (see  nodelal‐
>               loc mount option).
> 
> Is a bad interaction with `delalloc` still an issue and should we be using the `nodelalloc` option?

Apologies for not getting back to you right away.  I wanted to check
with some folks on the ext4 team, and in fact we talked about it at
this week's ext4 video chat.  Eric Whitney worked on fixing bigalloc
and delalloc, and it looks like the last of the fixes landed in Linux
version 5.4 in 2019.  So that warning in the ext4(5) man page is
definitely out of date.

I'll remove it in the next release of e2fsprogs.

Cheers,

					- Ted

Re: Does `-O bigalloc` still conflict with `delalloc`?

[Kiselev, Oleg]

Thank you, Ted!

On 5/27/22, 7:32 PM, "Theodore Ts'o" <tytso@mit.edu> wrote:

    CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.



    On Sat, May 21, 2022 at 02:39:00AM +0000, Kiselev, Oleg wrote:
    > The `ext4(5)` man page, contained in the most recent e2fsprogs still says:
    >
    >       Warning: The bigalloc feature is still under development, and may not be fully  supported
    >               with your kernel or may have various bugs.  Please see the web page http://ext4.wiki.ker‐
    >               nel.org/index.php/Bigalloc for details.  May clash with delayed allocation (see  nodelal‐
    >               loc mount option).
    >
    > Is a bad interaction with `delalloc` still an issue and should we be using the `nodelalloc` option?

    Apologies for not getting back to you right away.  I wanted to check
    with some folks on the ext4 team, and in fact we talked about it at
    this week's ext4 video chat.  Eric Whitney worked on fixing bigalloc
    and delalloc, and it looks like the last of the fixes landed in Linux
    version 5.4 in 2019.  So that warning in the ext4(5) man page is
    definitely out of date.

    I'll remove it in the next release of e2fsprogs.

    Cheers,

                                            - Ted