On 4/26/19 5:59 PM, Jorge Guerra wrote:
> From: Jorge Guerra <jorgeguerra@xxxxxx>
>
> While running the 'frag' command of 'xfs_db' we noticed that the
> tool is not scanning all the files in the file system. We noticed
> this when we modified the tool to print the inodes of all the files
> scanned. For example:
>
> $ find /mnt/xfsdisk -type f | wc -l
> 1782674
> $ xfs_db -r -c frag /dev/sdXX | grep MB | awk '{print $5}' | paste -s -d+ | bc
> 656818
>
> Upon inspecting the code we noticed that the scanfunc_ino function
> stops processing a given inode block once it encounters a free leaf.
> However, in practice we see that inodes are necessarily always layed
> out contiguously on the leaf node. This resulted in the 'frag'
> command skipping some valid inodes.
>
> In this change we modify the scanfunc_ino function to skip freed
> inodes. With the change in place we ran the same experiment again
> and noticed a more accurate file count:
>
> $ find /mnt/d0 -type f | wc -l
> 1810442
> $ xfs_db -r -c frag /dev/sdXX | grep MB | awk '{print $5}' | paste -s -d+ | bc
> 1810442
>
> Signed-off-by: Jorge Guerra <jorgeguerra@xxxxxx>
This looks right, but I'll warn you that xfs_db's frag command is largely
useless in the first place. ;)
Also, I think:
Fixes: 2a5eb70c ("xfs_db: teach the frag command about sparse inode chunks")
Reviewed-by: Eric Sandeen <sandeen@xxxxxxxxxx>
Thanks!
> ---
> db/frag.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/db/frag.c b/db/frag.c
> index 5f33cb73..91395234 100644
> --- a/db/frag.c
> +++ b/db/frag.c
> @@ -507,7 +507,7 @@ scanfunc_ino(
>
> for (j = 0; j < inodes_per_buf; j++) {
> if (XFS_INOBT_IS_FREE_DISK(&rp[i], ioff + j))
> - goto next_buf;
> + continue;
> dip = (xfs_dinode_t *)((char *)iocur_top->data +
> ((off + j) << mp->m_sb.sb_inodelog));
> process_inode(agf, agino + ioff + j, dip);
>
