Re: [PATCH 4/4] populate: improve runtime of __populate_fill_fs

[Zorro Lang <zlang@redhat.com>]

On Tue, Jan 17, 2023 at 04:44:33PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@kernel.org>
> 
> Run the copy loop in parallel to reduce runtime.  If filling the
> populated fs is selected (which it isn't by default in xfs/349), this
> reduces the runtime from ~18s to ~15s, since it's only making enough
> copies to reduce the free space by 5%.
> 
> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
> ---
>  common/populate |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> 
> diff --git a/common/populate b/common/populate
> index f34551d272..1c3c28463f 100644
> --- a/common/populate
> +++ b/common/populate
> @@ -151,8 +151,9 @@ __populate_fill_fs() {
>  	echo "FILL FS"
>  	echo "src_sz $SRC_SZ fs_sz $FS_SZ nr $NR"
>  	seq 2 "${NR}" | while read nr; do
> -		cp -pRdu "${dir}/test/1" "${dir}/test/${nr}"
> +		cp -pRdu "${dir}/test/1" "${dir}/test/${nr}" &
>  	done
> +	wait

I'm thinking about what'll happen if we do "Ctrl+c" on a running test which
is waiting for these cp operations.

>  }
>  
>  # For XFS, force on all the quota options if quota is enabled
>