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From: SeongJae Park <sj@kernel.org>
To: SeongJae Park <sj@kernel.org>
Cc: Barry Song <21cnbao@gmail.com>,
	Minchan Kim <minchan@kernel.org>,
	akpm@linux-foundation.org,
	damon@lists.linux.dev,
	linux-mm@kvack.org,
	linux-kernel@vger.kernel.org,
	mhocko@suse.com,
	hannes@cmpxchg.org,
	Barry Song <v-songbaohua@oppo.com>
Subject: Re: [PATCH RFC] mm: madvise: pageout: ignore references rather than clearing young
Date: Sat, 24 Feb 2024 12:12:21 -0800
Message-Id: <20240224201221.46450-1-sj@kernel.org>
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On Sat, 24 Feb 2024 11:07:23 -0800 SeongJae Park <sj@kernel.org> wrote:

> Hi Barry,
> 
> On Sat, 24 Feb 2024 12:37:59 +0800 Barry Song <21cnbao@gmail.com> wrote:
> 
> [...]
> > 
> > BTW\uff0c
> > Hi SeongJae,
> > I am not quite sure if damon also needs this, so I have kept damon as is by
> > setting ignore_references = false.  MADV_PAGEOUT is an explicit hint users
> > don't want the memory to be reclaimed, I don't know if it is true for damon as
> > well. If you have some comments, please chime in.
> 
> Thank you for calling my name :)
> 
> For DAMON's usecase, the document simply says the behavior would be same to
> MADV_PAGEOUT, so if we conclude to change MADV_PAGEOUT, I think same change
> should be made for DAMON's usecase, or update DAMON document.

Thanks to Barry's nice explanation on my other reply to the patch, now I think
the change is modest, and therefore I'd prefer the first way: Changing DAMON's
usecase, and keep the document as is.


Thanks,
SJ

> 
> 
> Thanks,
> SJ
> 
> > 
> > >
> > > Thanks.
> > 
> > Thanks
> > Barry