Messages in this thread | | | Date | Wed, 27 Jun 2007 11:13:52 -0700 (PDT) | From | Davide Libenzi <> | Subject | Re: [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
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |