Messages in this thread | | | Date | Tue, 1 Mar 2011 15:41:00 -0800 | From | Andrew Morton <> | Subject | Re: [PATCH] ksm: add vm_stat and meminfo entry to reflect pte mapping to ksm pages |
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On Sat, 26 Feb 2011 22:56:31 +0800 Nai Xia <nai.xia@gmail.com> wrote:
> ksm_pages_sharing is updated by ksmd periodically. In some cases, it cannot > reflect the actual savings and makes the benchmarks on volatile VMAs very > inaccurate. > > This patch add a vm_stat entry and let the /proc/meminfo show information > about how much virutal address pte is being mapped to ksm pages. With default > ksm paramters (pages_to_scan==100 && sleep_millisecs==20), this can result in > 50% more accurate averaged savings result for the following test program. > Bigger sleep_millisecs values will increase this deviation.
So I think you're saying that the existing ksm_pages_sharing sysfs file is no good.
You added a new entry to /proc/meminfo and left ksm_pages_sharing as-is. Why not leave /proc/meminfo alone, and fix up the existing ksm_pages_sharing?
Also, the patch accumulates the NR_KSM_PAGES_SHARING counts on a per-zone basis as well as on a global basis, but only provides the global count to userspace. The per-zone counts are potentially interesting? If not, maintaining the per-zone counters is wasted overhead.
> > --- test.c----- >
The "^---" token conventionally means "end of changelog". Please avoid inserting it into the middle of the changelog.
> +++ b/mm/ksm.c > @@ -897,6 +897,7 @@ static int try_to_merge_one_page(struct vm_area_struct > *vma,
Your email client wordwraps the patches.
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