Re: [PATCH] Documentation/mm/page_owner.rst: update experimental data

From: Jonathan Corbet
Date: Thu Aug 25 2022 - 14:09:53 EST


Yixuan Cao <caoyixuan2019@xxxxxxxxxxxxxxxx> writes:

> I noticed some experimental data need to be updated.
>
> Signed-off-by: Yixuan Cao <caoyixuan2019@xxxxxxxxxxxxxxxx>
> ---
> Documentation/mm/page_owner.rst | 12 ++++++------
> 1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/Documentation/mm/page_owner.rst b/Documentation/mm/page_owner.rst
> index f18fd8907049..8e2545bb4e17 100644
> --- a/Documentation/mm/page_owner.rst
> +++ b/Documentation/mm/page_owner.rst
> @@ -41,17 +41,17 @@ size change due to this facility.
> - Without page owner::
>
> text data bss dec hex filename
> - 48392 2333 644 51369 c8a9 mm/page_alloc.o
> + 58581 3166 652 62399 f3bf mm/page_alloc.o
>
> - With page owner::
>
> text data bss dec hex filename
> - 48800 2445 644 51889 cab1 mm/page_alloc.o
> - 6662 108 29 6799 1a8f mm/page_owner.o
> - 1025 8 8 1041 411 mm/page_ext.o
> + 59085 3294 652 63031 f637 mm/page_alloc.o
> + 7464 125 28 7617 1dc1 mm/page_owner.o
> + 1396 32 8 1436 59c mm/page_ext.o
>
> -Although, roughly, 8 KB code is added in total, page_alloc.o increase by
> -520 bytes and less than half of it is in hotpath. Building the kernel with
> +Although, roughly, 9 KB code is added in total, page_alloc.o increase by
> +632 bytes and less than half of it is in hotpath. Building the kernel with
> page owner and turning it on if needed would be great option to debug
> kernel memory problem.

This seems like a fine patch...but I do have to wonder if it really
makes sense to maintain this information, which will surely be subject
to frequent change. Perhaps the whole thing is better replaced with a
line saying that enabling page owner adds ~9KB?

Thanks,

jon