Re: [PATCH v3 1/4] btrfs/301: Make the test compatible with all the supported block sizes

[Disha Goel <disgoel@linux.ibm.com>]

On 20/08/25 1:45 pm, Nirjhar Roy (IBM) wrote:
> With large block sizes like 64k the test failed with the
> following logs:
> 
>       QA output created by 301
>       basic accounting
>      +subvol 256 mismatched usage 33947648 vs 4587520 (expected data 4194304 expected meta 393216 diff 29360128)
>      +subvol 256 mismatched usage 168165376 vs 138805248 (expected data 138412032 expected meta 393216 diff 29360128)
>      +subvol 256 mismatched usage 33947648 vs 4587520 (expected data 4194304 expected meta 393216 diff 29360128)
>      +subvol 256 mismatched usage 33947648 vs 4587520 (expected data 4194304 expected meta 393216 diff 29360128)
>       fallocate: Disk quota exceeded
> 
> The test creates nr_fill files each of size 8k. Now with 64k
> block size, 8k sized files occupy more than the expected sizes (i.e, 8k)
> due to internal fragmentation, since 1 file will occupy at least 1
> fsblock. Fix this by making the file size 64k, which is aligned
> with all the supported block sizes.
> 
> Reviewed-by: Qu Wenruo <wqu@suse.com>
> Reported-by: Disha Goel <disgoel@linux.ibm.com>
> Signed-off-by: Nirjhar Roy (IBM) <nirjhar.roy.lists@gmail.com>

I tested it on Power, and the btrfs/301 test passes with both 4k & 64k 
block sizes.

SECTION       -- btrfs_64k
RECREATING    -- btrfs on /dev/loop0
FSTYP         -- btrfs
PLATFORM      -- Linux/ppc64le localhost 6.17.0-rc2-00060-g068a56e56fa8 
#3 SMP Thu Aug 21 17:54:04 IST 2025
MKFS_OPTIONS  -- -f -s 65536 -n 65536 /dev/loop1
MOUNT_OPTIONS -- /dev/loop1 /mnt/scratch

btrfs/301 67s ...  111s
Ran: btrfs/301
Passed all 1 tests

Tested-by: Disha Goel <disgoel@linux.ibm.com>

> ---
>   tests/btrfs/301 | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tests/btrfs/301 b/tests/btrfs/301
> index 6b59749d..be346f52 100755
> --- a/tests/btrfs/301
> +++ b/tests/btrfs/301
> @@ -23,7 +23,7 @@ subv=$SCRATCH_MNT/subv
>   nested=$SCRATCH_MNT/subv/nested
>   snap=$SCRATCH_MNT/snap
>   nr_fill=512
> -fill_sz=$((8 * 1024))
> +fill_sz=$((64 * 1024))
>   total_fill=$(($nr_fill * $fill_sz))
>   nodesize=$($BTRFS_UTIL_PROG inspect-internal dump-super $SCRATCH_DEV | \
>   					grep nodesize | $AWK_PROG '{print $2}')