Re: [PATCH 0/2 v6] add ioctl/sysfs to donate file-backed pages

From: Jaegeuk Kim
Date: Fri Jan 17 2025 - 15:37:19 EST


On 01/17, Matthew Wilcox wrote:
> 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?

Yeah, the intention looks similar like marking it cold and paging out later.