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X-FangMail-Envelope: 1672020447/4NgLlM1bT9z4xyCV/63A901DF.000/10.5.228.132/[10.5.228.132]/mse-fl1.zte.com.cn/ X-Fangmail-Anti-Spam-Filtered: true X-Fangmail-MID-QID: 63A901DF.000/4NgLlM1bT9z4xyCV X-Spam-Status: No, score=0.6 required=5.0 tests=BAYES_00,SORTED_RECIPS, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1753241278718779527?= X-GMAIL-MSGID: =?utf-8?q?1753241278718779527?= From: xu xin 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. Cc: Xiaokai Ran Cc: Yang Yang Cc: Jiang Xuexin Cc: Claudio Imbrenda Cc: David Hildenbrand Signed-off-by: xu xin --- Documentation/admin-guide/mm/ksm.rst | 7 +++++++ 1 file changed, 7 insertions(+) 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``