Re: [PATCH] Physical Memory Management [0/1]

[MichaÅ Nazarewicz]

> On Thu, 2009-05-14 at 11:00 +0200, MichaÅ 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.

-- 
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 .o. | Liege of Serenly Enlightened Majesty of         o' \,=./ `o
 ..o | Computer Science,  MichaÅ "mina86" Nazarewicz      (o o)
 ooo +-<m.nazarewicz@xxxxxxxxxxx>-<mina86@xxxxxxxxxx>-ooO--(_)--Ooo--

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