On 22.05.23 12:52, Yang Yang wrote:
From: xu xin <xu.xin16@xxxxxxxxxx> 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