Hi.
On Thu, Apr 27, 2023 at 03:45:21PM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@xxxxxxxxxx>
>
> The slack calculation for per-AG btrees is a bit inaccurate because it
> only disables slack space in the new btrees when the amount of free
> space in the AG (not counting the btrees) is less than 3/32ths of the
> AG. In other words, it assumes that the btrees will fit in less than 9
> percent of the space.
.
.
.
>
> Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
This looks fine, with a small caveat below...
.
.
.
> +
> +static xfs_extlen_t
> +estimate_allocbt_blocks(
> + struct xfs_perag *pag,
> + unsigned int nr_extents)
> +{
> + return libxfs_allocbt_calc_size(pag->pag_mount, nr_extents) * 2;
> +}
Forgive my ignorance here, but what's the reason of the magic number? It seems
to me by multiplying by 2 here, you are considering a split of every single
leaf for the calculated btree size, but I'm not sure if that's the intention,
could you please confirm or correct me? :)
Other than that, the patch looks good
Reviewed-by: Carlos Maiolino <cmaiolino@xxxxxxxxxx>
--
Carlos Maiolino
