Re: Question about the "EXPERIMENTAL" tag for dax in XFS

[Darrick J. Wong]

On Fri, Feb 26, 2021 at 09:45:45AM +0000, ruansy.fnst@xxxxxxxxxxx wrote:
> Hi, guys
> 
> Beside this patchset, I'd like to confirm something about the
> "EXPERIMENTAL" tag for dax in XFS.
> 
> In XFS, the "EXPERIMENTAL" tag, which is reported in waring message
> when we mount a pmem device with dax option, has been existed for a
> while.  It's a bit annoying when using fsdax feature.  So, my initial
> intention was to remove this tag.  And I started to find out and solve
> the problems which prevent it from being removed.
> 
> As is talked before, there are 3 main problems.  The first one is "dax
> semantics", which has been resolved.  The rest two are "RMAP for
> fsdax" and "support dax reflink for filesystem", which I have been
> working on.  

<nod>

> So, what I want to confirm is: does it means that we can remove the
> "EXPERIMENTAL" tag when the rest two problem are solved?

Yes.  I'd keep the experimental tag for a cycle or two to make sure that
nothing new pops up, but otherwise the two patchsets you've sent close
those two big remaining gaps.  Thank you for working on this!

> Or maybe there are other important problems need to be fixed before
> removing it?  If there are, could you please show me that?

That remains to be seen through QA/validation, but I think that's it.

Granted, I still have to read through the two patchsets...

--D

> 
> Thank you.
> 
> 
> --
> Ruan Shiyang.