RE: [RFC PATCH] Introduce generalized data temperature estimation framework

[Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>]

On Wed, 2025-01-29 at 11:23 +0100, Hans Holmberg wrote:
> On Tue, Jan 28, 2025 at 11:31 PM Viacheslav Dubeyko
> <Slava.Dubeyko@ibm.com> wrote:
> > 
> > 

<skipped>

> > > 
> > 
> > Another trouble here. What is the way to measure write amplification, from your
> > point of view? Which benchmarking tool or framework do you suggest for write
> > amplification estimation?
> 
> FDP drives expose this information. You can retrieve the stats using
> the nvme cli.

Do you mean that FDP drives has some additional info in S.M.A.R.T subsystem?
Does it some special subsystem in FDP drives? Is it regular statistics or some
debug feature of the device?

> If you are using zoned storage, you can add write amp metrics inside
> the file system
> or just measure the amount of blocks written to the device using iostat.
> 

I see the point with iostat or blktrace, for example. But what do you imply by
adding write amp metric inside the file system? Especially, if you are
mentioning zoned storage. What is the difference here between conventional and
zoned storage devices?

Thanks,
Slava.