Re: [PATCH v7 0/3] FDP and per-io hints

Christoph Hellwig
2024-10-14T07:47:14Z

On Mon, Oct 14, 2024 at 07:02:11AM +0000, Javier Gonzalez wrote:
> > And exactly that is the problem. For file systems we can't support
> > that sanely. So IFF you absolutely want the per-I/O hints we need
> > an opt in by the file operations. I've said that at least twice
> > in this discussion before, but as everyone likes to have political
> > discussions instead of technical ones no one replied to that.
>
> Is it a way forward to add this in a new spin of the series - keeping the
> temperature mapping on the NVMe side?

What do you gain from that? NVMe does not understand data temperatures,
so why make up that claim? Especially as it directly undermindes any
file system work to actually make use of it.

> If not, what would be acceptable for a first version, before getting into adding
> a new interface to expose agnostic hints?

Just iterate on Kanchan's series for a block layer (and possible user level,
but that's less urgent) interface for stream separation?