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    SubjectRe: [patch 2/3] MAP_NOZERO - implement sys_brk2()
    On Wed, 27 Jun 2007, Hugh Dickins wrote:

    > In honesty, I should add that I dislike and distrust Davide's
    > MAP_NOZERO very much indeed! Would much rather leave my cpus
    > spending a little time in clear_page(). A uid in struct page
    > (though I'm sure we could find somewhere to tuck it away) -
    > the horror, the horror! But I've so far failed to find a killer
    > argument against it, and am hoping for someone else to do so.

    Little time? Please, do not trust me. Start oprofile and run a kernel
    build. Look, I'm not even talking about som micro benchmark explicitly
    built to exploit the thing. A kernel build.
    You will find clear_page to be the *1st* kernel entry after cc1 and as.
    That is bad for two reasons. The time it spends in there, and the cache it
    blows.



    - Davide


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