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From:   Leonard Foerster <foersleo@amazon.com>
To:     SeongJae Park <sjpark@amazon.com>
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Subject: Re: [PATCH v16 04/14] mm/damon: Adaptively adjust regions
Date:   Thu, 18 Jun 2020 11:23:38 +0200
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On 2020-06-15T18:19:17+02:00 SeongJae Park <sjpark@amazon.com> wrote:

> From: SeongJae Park <sjpark@amazon.de>
> 
> Even somehow the initial monitoring target regions are well constructed
> to fulfill the assumption (pages in same region have similar access
> frequencies), the data access pattern can be dynamically changed.  This
> will result in low monitoring quality.  To keep the assumption as much
> as possible, DAMON adaptively merges and splits each region.
> 
> For each ``aggregation interval``, it compares the access frequencies of
> adjacent regions and merges those if the frequency difference is small.
> Then, after it reports and clears the aggregated access frequency of
> each region, it splits each region into two or third regions of random
> size, if the total number of regions after the splits wouldn't exceed
> the user-specified maximum number of regions.
> 
> In this way, DAMON provides its best-effort quality and minimal overhead
> while keeping the overhead bound.
> 
> Signed-off-by: SeongJae Park <sjpark@amazon.de>
> ---

Reviewed-by: Leonard Foerster <foersleo@amazon.de>