lkml.org 
[lkml]   [2008]   [Sep]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [RFC][PATCH] Remove cgroup member from struct page (v3)
    On Wed, 17 Sep 2008 18:40:08 -0700
    Andrew Morton <akpm@linux-foundation.org> wrote:
    > > Advantages of the patch
    > >
    > > 1. It removes the extra pointer in struct page
    > >
    > > Disadvantages
    > >
    > > 1. Radix tree lookup is not an O(1) operation, once the page is known
    > > getting to the page_cgroup (pc) is a little more expensive now.
    >
    > Why are we doing this? I can guess, but I'd rather not have to.
    >
    > a) It's slower.
    >
    > b) It uses even more memory worst-case.
    >
    > c) It uses less memory best-case.
    >
    > someone somewhere decided that (Aa + Bb) / Cc < 1.0. What are the values
    > of A, B and C and where did they come from? ;)
    >

    Balbir, don't you like pre-allocate-page-cgroup-at-boot at all ?
    I don't like radix-tree for objects which can spread to very vast/sparse area ;)

    BTW, I already have lazy-lru-by-pagevec protocol on my patch(hash version) and
    seems to work well. I'm now testing it and will post today if I'm enough lucky.

    Thanks,
    -Kame



    \
     
     \ /
      Last update: 2008-09-18 06:45    [W:4.666 / U:0.052 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site