Messages in this thread | | | Date | Tue, 23 May 2023 11:51:09 +0200 | Subject | Re: [PATCH v8 2/6] ksm: count all zero pages placed by KSM | From | David Hildenbrand <> |
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On 22.05.23 12:52, Yang Yang wrote: > From: xu xin <xu.xin16@zte.com.cn> > > As pages_sharing and pages_shared don't include the number of zero pages > merged by KSM, we cannot know how many pages are zero pages placed by KSM > when enabling use_zero_pages, which leads to KSM not being transparent with > all actual merged pages by KSM. In the early days of use_zero_pages, > zero-pages was unable to get unshared by the ways like MADV_UNMERGEABLE so > it's hard to count how many times one of those zeropages was then unmerged. > > But now, unsharing KSM-placed zero page accurately has been achieved, so we > can easily count both how many times a page full of zeroes was merged with > zero-page and how many times one of those pages was then unmerged. and so, > it helps to estimate memory demands when each and every shared page could > get unshared. > > So we add ksm_zero_pages under /sys/kernel/mm/ksm/ to show the number > of all zero pages placed by KSM. > > v7->v8: > Handle the case when khugepaged replaces a shared zeropage by a THP. >
Oh, and just a note, such version comments should go below the "--", such that they will automatically get dropped when applying the patch.
(Usually, version information in the cover letter is sufficient :) )
-- Thanks,
David / dhildenb
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