Re: [PATCH RESEND 0/6] support ksm_stat showing at cgroup level

[David Hildenbrand <david@redhat.com>]

On 22.04.25 13:14, xu.xin16@zte.com.cn wrote:
> From: xu xin <xu.xin16@zte.com.cn>
> 
> With the enablement of container-level KSM (e.g., via prctl [1]), there is
> a growing demand for container-level observability of KSM behavior. However,
> current cgroup implementations lack support for exposing KSM-related
> metrics.
> 
> This patch introduces a new interface named ksm_stat
> at the cgroup hierarchy level, enabling users to monitor KSM merging
> statistics specifically for containers where this feature has been
> activated, eliminating the need to manually inspect KSM information for
> each individual process within the cgroup.
> 
> Users can obtain the KSM information of a cgroup just by:
> 
> # cat /sys/fs/cgroup/memory.ksm_stat
> ksm_rmap_items 76800
> ksm_zero_pages 0
> ksm_merging_pages 76800
> ksm_process_profit 309657600
> 
> Current implementation supports cgroup v1 temporarily; cgroup v2
> compatibility is planned for future versions.

As raised by Willy, we focus on v2.

Independent of that, I strongly assume that 
Documentation/admin-guide/cgroup-v1/memory.rst needs care :)

-- 
Cheers,

David / dhildenb