From: xu xin Date: Fri, 30 Dec 2022 01:17:28 +0000 (+0800) Subject: ksm: add zero_pages_sharing documentation X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=291d698d0e6da7f0f6798bea84c883a1c1de0b61;p=users%2Fjedix%2Flinux-maple.git ksm: add zero_pages_sharing documentation When enabling use_zero_pages, pages_sharing cannot represent how much memory saved indeed. zero_pages_sharing + pages_sharing does. add the description of zero_pages_sharing. Link: https://lkml.kernel.org/r/202212300917284911971@zte.com.cn Signed-off-by: xu xin Cc: Xiaokai Ran Cc: Yang Yang Cc: Jiang Xuexin Cc: Claudio Imbrenda Cc: David Hildenbrand Signed-off-by: Andrew Morton --- diff --git a/Documentation/admin-guide/mm/ksm.rst b/Documentation/admin-guide/mm/ksm.rst index fb6ba2002a4b..f160f9487a90 100644 --- a/Documentation/admin-guide/mm/ksm.rst +++ b/Documentation/admin-guide/mm/ksm.rst @@ -173,6 +173,13 @@ stable_node_chains the number of KSM pages that hit the ``max_page_sharing`` limit stable_node_dups number of duplicated KSM pages +zero_pages_sharing + how many empty pages are sharing kernel zero page(s) instead of + with each other as it would happen normally. Only effective when + enabling ``use_zero_pages`` knob. + +When enabling ``use_zero_pages``, the sum of ``pages_sharing`` + +``zero_pages_sharing`` represents how much really saved by KSM. A high ratio of ``pages_sharing`` to ``pages_shared`` indicates good sharing, but a high ratio of ``pages_unshared`` to ``pages_sharing``