linux-kernel - Re: [PATCH v29 05/13] mm/damon: Implement primitives for the virtual memory address spaces

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Message-ID: <3da2bb79-4448-4857-a9d1-698a360c51a2@amazon.com>
Date:   Tue, 25 May 2021 17:19:04 +0200
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Subject: Re: [PATCH v29 05/13] mm/damon: Implement primitives for the virtual
 memory address spaces

Hi SeongJae,

Some questions for this patch:

Why do we split the regions in 3 areas (heap, stack, mmaped)? I 
understand we don't want to model the whole virtual address space, but 
why don't we just use whatever is modeled by the VMAs to define the 
regions boundaries?

I am not quite understanding why we both set the page idle and young (in 
damon_ptep_mkold). For WSS computation on our end we have used 
pte_clear_young_notify. Why do we touch the page idle flag at all? What 
flags do the reclaim logic use to track access?

Kind regards,

Fernand