Re: [PATCH 1/5] xfs: don't treat append-only files as having preallocations

Christoph Hellwig
2024-06-17T06:46:08Z

On Mon, Jun 17, 2024 at 03:03:28PM +1000, Dave Chinner wrote:
> > That case should be covered by the XFS_IDIRTY_RELEASE, at least
> > except for O_SYNC workloads.
>
> Ah, so I fixed the problem independently 7 or 8 years later to fix
> Linux NFS server performance issues. Ok, that makes removing the
> flag less bad, but I still don't see the harm in keeping it there
> given that behaviour has existed for the past 20 years....

I'm really kinda worried about these unaccounted preallocations lingering
around basically forever. Note that in current mainline there actually
is a path removing them more or less accidentally when there are
delalloc blocks in a can_free_eofblocks path with force == true,
but that's going away with the next patch.