lkml.org 
[lkml]   [2009]   [Aug]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 1/4] compcache: xvmalloc memory allocator
    On Tue, 25 Aug 2009, Nitin Gupta wrote:

    > PFNs are 32-bit on all archs while for 'struct page *', we require 32-bit or
    > 64-bit depending on arch. ramzswap allocates a table entry <pagenum, offset>
    > corresponding to every swap slot. So, the size of table will unnecessarily
    > increase on 64-bit archs. Same is the argument for xvmalloc free list sizes.

    Wrong. PFNs must be longer than 32 bit otherwise a system cannot
    address more than 2^12 + 2^32 = 2^44 => 16TB.

    The type used for PFNs is unsigned long which are 64 bit on 64 bit platforms.



    \
     
     \ /
      Last update: 2009-08-26 18:11    [W:0.022 / U:180.944 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site