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    SubjectRe: [RFC 00/15] x86_64: Optimize percpu accesses
    Christoph Lameter wrote:
    >
    > There will be no additional overhead since the memory already mapped 1-1 using 2MB TLBs and we want to use the same for the percpu areas. This is similar to the vmemmap solution.
    >

    THAT sounds strange. If you're using dedicated virtual maps (which is
    what you're responding to here) then you will *always* have additional
    TLB pressure. Furthermore, if you use 2 MB pages, you:

    a) can only allocate full 2 MB pages, which is expensive for the static
    users and difficult for the dynamic users;

    b) increase pressure in the relatively small 2 MB TLB.

    -hpa


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