Re: [PATCH 0/5] Reduce size of extent_io_tree, remove fs_info

[Josef Bacik <josef@toxicpanda.com>]

On Tue, Nov 21, 2023 at 02:20:12PM +0100, David Sterba wrote:
> We have the fs_info pointer in extent_io_tree for the trace points as
> the inode is not always set. This is a bit wasteful and extent_io_tree
> is also embedded in other structures. The tree owner can be used to
> determine if the inode is expected to be non-NULL, otherwise we can
> store the fs_info pointer.
> 
> I tried to do it in the cleanest way, union and access wrappers, it's
> IMO worth the space savings:
> 
> - btrfs_inode		1104 -> 1088
> - btrfs_device		 520 ->  512
> - btrfs_root		1360 -> 1344
> - btrfs_transaction	 456 ->  440
> - btrfs_fs_info		3600 -> 3592
> - reloc_control		1520 -> 1512
> 
> The btrfs_inode structure is getting closer to the 1024 size where it
> would pack better in the slab pages.
>

Reviewed-by: Josef Bacik <josef@toxicpanda.com>

Thanks,

Josef