Re: [PATCH RFC v2 4/4] mm/ksm: add force merging/unmerging documentation

From: Timofey Titovets
Date: Tue May 14 2019 - 20:56:16 EST


LGTM for whole series

Reviewed-by: Timofey Titovets <nefelim4ag@xxxxxxxxx>

ÐÑ, 14 ÐÐÑ 2019 Ð. Ð 16:17, Oleksandr Natalenko <oleksandr@xxxxxxxxxx>:
>
> Document respective sysfs knob.
>
> Signed-off-by: Oleksandr Natalenko <oleksandr@xxxxxxxxxx>
> ---
> Documentation/admin-guide/mm/ksm.rst | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/Documentation/admin-guide/mm/ksm.rst b/Documentation/admin-guide/mm/ksm.rst
> index 9303786632d1..4302b92910ec 100644
> --- a/Documentation/admin-guide/mm/ksm.rst
> +++ b/Documentation/admin-guide/mm/ksm.rst
> @@ -78,6 +78,17 @@ KSM daemon sysfs interface
> The KSM daemon is controlled by sysfs files in ``/sys/kernel/mm/ksm/``,
> readable by all but writable only by root:
>
> +force_madvise
> + write-only control to force merging/unmerging for specific
> + task.
> +
> + To mark the VMAs as mergeable, use:
> + ``echo PID > /sys/kernel/mm/ksm/force_madvise``
> +
> + To unmerge all the VMAs, use:
> + ``echo -PID > /sys/kernel/mm/ksm/force_madvise``
> + (note the prepending "minus")
> +
In patch 3/4 you have special case with PID 0,
may be that also must be documented here?

> pages_to_scan
> how many pages to scan before ksmd goes to sleep
> e.g. ``echo 100 > /sys/kernel/mm/ksm/pages_to_scan``.
> --
> 2.21.0
>


--
Have a nice day,
Timofey.