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    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.

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      Last update: 2009-08-26 18:11    [W:0.027 / U:34.396 seconds]
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