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	Fri, 17 Jan 2025 19:04:26 +0000
Date: Fri, 17 Jan 2025 19:04:26 +0000
From: Matthew Wilcox <willy@infradead.org>
To: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net,
	linux-mm@kvack.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 0/2 v6] add ioctl/sysfs to donate file-backed pages
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References: <20250117164350.2419840-1-jaegeuk@kernel.org>
 <Z4qb9Pv-mEQZrrXc@casper.infradead.org>
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On Fri, Jan 17, 2025 at 06:48:55PM +0000, Jaegeuk Kim wrote:
> > I don't understand how this is different from MADV_COLD.  Please
> > explain.
> 
> MADV_COLD is a vma range, while this is a file range. So, it's more close to
> fadvise(POSIX_FADV_DONTNEED) which tries to reclaim the file-backed pages
> at the time when it's called. The idea is to keep the hints only, and try to
> reclaim all later when admin expects system memory pressure soon.

So you're saying you want POSIX_FADV_COLD?