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

Jaegeuk Kim
2025-02-04T16:29:40Z

On 01/17, Jaegeuk Kim wrote:
> 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.

Kindly ping, for the feedback on the direction. If there's demand for something
generalized api, I'm happy to explore.