Re: [PATCH v2 00/13] forcealign for xfs

Christoph Hellwig
2024-07-06T07:53:57Z

On Fri, Jul 05, 2024 at 04:24:37PM +0000, John Garry wrote:
> The actual forcealign patches are the same in this series, modulo an
> attempt for a fix in xfs_bunmapi_align().
>
> Why forcealign?
> In some scenarios to may be required to guarantee extent alignment and
> granularity.
>
> For example, for atomic writes, the maximum atomic write unit size would
> be limited at the extent alignment and granularity, guaranteeing that an
> atomic write would not span data present in multiple extents.
>
> forcealign may be useful as a performance tuning optimization in other
> scenarios.

From previous side discussion I know Dave disagrees, but given how
much pain the larger than FSB rtextents have caused I'm very skeptical
if taking this on is the right tradeoff.