On Wed, Aug 24, 2022 at 07:08:21AM +0000, xu xin wrote: > +1) How to determine whether KSM save memory or consume memory in system-wide > +range? Here is a simple approximate calculation for reference: > + > + general_profit =~ pages_sharing * sizeof(page) - (all_rmap_items) * > + sizeof(rmap_item); > + > +where all_rmap_items can be easily obtained by summing ``pages_sharing``, > +``pages_shared``, ``pages_unshared`` and ``pages_volatile``. > + > +2) The KSM profit inner a single process can be similarly obtained by the > +following approximate calculation: > + > + process_profit =~ ksm_merging_sharing * sizeof(page) - > + ksm_rmp_items * sizeof(rmap_item). > + The profit formula above can be put into code blocks. Also, align the numbered list texts, like: ---- >8 ---- diff --git a/Documentation/admin-guide/mm/ksm.rst b/Documentation/admin-guide/mm/ksm.rst index 40bc11f6fa15fa..7e3092fe407e37 100644 --- a/Documentation/admin-guide/mm/ksm.rst +++ b/Documentation/admin-guide/mm/ksm.rst @@ -194,22 +194,22 @@ be merged, but some may not be abled to be merged after being checked several times, which are unprofitable memory consumed. 1) How to determine whether KSM save memory or consume memory in system-wide -range? Here is a simple approximate calculation for reference: + range? Here is a simple approximate calculation for reference:: general_profit =~ pages_sharing * sizeof(page) - (all_rmap_items) * sizeof(rmap_item); -where all_rmap_items can be easily obtained by summing ``pages_sharing``, -``pages_shared``, ``pages_unshared`` and ``pages_volatile``. + where all_rmap_items can be easily obtained by summing ``pages_sharing``, + ``pages_shared``, ``pages_unshared`` and ``pages_volatile``. 2) The KSM profit inner a single process can be similarly obtained by the -following approximate calculation: + following approximate calculation:: process_profit =~ ksm_merging_sharing * sizeof(page) - ksm_rmp_items * sizeof(rmap_item). -where both ksm_merging_sharing and ksm_rmp_items are shown under the directory -``/proc/<pid>/``. + where both ksm_merging_sharing and ksm_rmp_items are shown under the + directory ``/proc/<pid>/``. From the perspective of application, a high ratio of ``ksm_rmp_items`` to ``ksm_merging_sharing`` means a bad madvise-applied policy, so developers or Thanks. -- An old man doll... just what I always wanted! - Clara
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