Re: [PATCH 0/7] ext4: Convert truncated extent data to inline data.

From: Julian Sun
Date: Tue Jan 07 2025 - 01:04:14 EST


Jan Kara <jack@xxxxxxx> 于2025年1月6日周一 23:51写道:
>
> On Fri 20-12-24 23:16:18, Julian Sun wrote:
> > Ext4 provides the feature of storing data inline and automatically
> > converts it to extent data when appropriate. However, files stored
> > as extents cannot be converted back to inline data after truncation,
> > even if the file size allows for inline data storage.
> > This patch set implements the feature to store large truncated files
> > as inline data when suitable, improving disk utilization.
> > Patches 1-3 include some cleanups and fixes.
> > Patches 4-6 refactor the functions responsible for writing inline data,
> > consolidating their logic for better code organization.
> > Patch 7 implements the feature of storing truncated files as inline data
> > on the next write operation.
>
> Thanks for the patches! So ext4 inline data feature is a bit problematic
> and has some locking issues in the implementation which we didn't manage to
> fix [1]. We are even considering just disabling this feature due to the
> complications with it. Hence I don't quite like further complicating this
> code by adding possibility to create inline data in an inode after it had
> data blocks allocated. That being said I like the preparatory cleanups in
> this patch series. These are useful regardless of the feature itself.

Ok. It looks fine to me. Thank you for your clarification.
>
> Honza
>
> [1] See our attempts in thread:
> https://lore.kernel.org/all/d704ce55-321a-9c1d-1f8b-3360a0fdf978@xxxxxxxxxx
>
> --
> Jan Kara <jack@xxxxxxxx>
> SUSE Labs, CR


Thanks,
--
Julian Sun <sunjunchao2870@xxxxxxxxx>