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LK embedded kernel
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What is PMM/PMM arena? #283

Closed lattice0 closed 3 years ago

lattice0 commented 3 years ago

Hello, I have a simple question. What PMM stands for? What is a PMM arena? Can't find any of these concepts on google.

Thanks!

travisg commented 3 years ago

Ah, the PMM is the 'physical memory manager'. In a system where there's a paging memory management unit (MMU) it is the part the tracks the allocated and free physical memory pages. The VMM is the virtual memory manager, and it allocates and frees pages from the PMM.

A PMM Arena is a single run of physical memory. Say on a computer with 2GB ram it may be from address 0 to 0x80000000. There may be more than one arena if physical memory is chopped into multiple chunks, which is fairly common on PCs at least.

On Mon, Nov 16, 2020 at 6:10 PM Lucas Zanela notifications@github.com wrote:

Hello, I have a simple question. What PMM stands for? What is a PMM arena? Can't find any of these concepts on google.

Thanks!

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