Re: [PATCH v1] generic/476: requires 27GB scratch size

["xuyang2018.jy@fujitsu.com" <xuyang2018.jy@fujitsu.com>]

on 2022/07/21 10:29, bxue@redhat.com wrote:
> From: Boyang Xue <bxue@redhat.com>
> 
> The test requires larger scratch dev size when running on top of NFS other
> than ext4 and xfs. It requires at least 27GB in my test. Without this
> requirement, the test run never finishes on NFS, leaving 100% scratch disk
> space use.
> 
> Signed-off-by: Boyang Xue <bxue@redhat.com>
> ---
> Hi,
> 
> I find generic/476 easily goes into an infinite run on top of NFS. When it
> happens, the common pattern is 100% disk space use of SCRATCH_MNT, and
> `nfsiostat` shows 50% write error on SCRATCH_MNT. When I run it with a large
> enough SCRATCH_MNT, the problem disappears. So I post this patch to add the size
> requirement.
> 
> Please help review this patch. Thanks!
> 
> -Boyang
> 
>   tests/generic/476 | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/tests/generic/476 b/tests/generic/476
> index 212373d1..dcc7c3da 100755
> --- a/tests/generic/476
> +++ b/tests/generic/476
> @@ -24,6 +24,7 @@ _cleanup()
>   _supported_fs generic
>   
>   _require_scratch
> +_require_scratch_size $((27 * 1024 * 1024)) # 27GB

If NFS needs this requirement, why do you require all filesystem meet this?

It will break test when using local filesystem ie xfs,ext4(as README 
says the minimum requiremount is 10G). I often use 20G as test device 
and scratch device.

Also, I think you should figure out why NFS 100% use space. Use a large
device size only hides a bug.

Best Regards
Yang Xu
>   _require_command "$KILLALL_PROG" "killall"
>   
>   echo "Silence is golden."