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    SubjectRe: [PATCH] Physical Memory Management [0/1]
    > On Thu, 2009-05-14 at 11:00 +0200, Michał Nazarewicz wrote:
    >> PMM solves this problem since the buffers are allocated when they
    >> are needed.

    On Thu, 14 May 2009 13:20:02 +0200, Peter Zijlstra wrote:
    > Ha - only when you actually manage to allocate things. Physically
    > contiguous allocations are exceedingly hard once the machine has been
    > running for a while.

    PMM reserves memory during boot time using alloc_bootmem_low_pages().
    After this is done, it can allocate buffers from reserved pool.

    The idea here is that there are n hardware accelerators, each
    can operate on 1MiB blocks (to simplify assume that's the case).
    However, we know that at most m < n devices will be used at the same
    time so instead of reserving n MiBs of memory we reserve only m MiBs.

    --
    Best regards, _ _
    .o. | Liege of Serenly Enlightened Majesty of o' \,=./ `o
    ..o | Computer Science, Michał "mina86" Nazarewicz (o o)
    ooo +-<m.nazarewicz@samsung.com>-<mina86@jabber.org>-ooO--(_)--Ooo--

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