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Date:   Tue, 19 Oct 2021 02:16:27 +0300
From:   "Kirill A. Shutemov" <kirill@shutemov.name>
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     Matthew Wilcox <willy@infradead.org>,
        Kent Overstreet <kent.overstreet@gmail.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        "Darrick J. Wong" <djwong@kernel.org>,
        Christoph Hellwig <hch@infradead.org>,
        David Howells <dhowells@redhat.com>,
        Hugh Dickins <hughd@google.com>
Subject: Re: Folios for 5.15 request - Was: re: Folio discussion recap -
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On Mon, Oct 18, 2021 at 05:56:34PM -0400, Johannes Weiner wrote:
> > I don't think there will ever be consensus as long as you don't take
> > the concerns of other MM developers seriously.  On Friday's call, several
> > people working on using large pages for anon memory told you that using
> > folios for anon memory would make their lives easier, and you didn't care.
> 
> Nope, one person claimed that it would help, and I asked how. Not
> because I'm against typesafety, but because I wanted to know if there
> is an aspect in there that would specifically benefit from a shared
> folio type. I don't remember there being one, and I'm not against type
> safety for anon pages.
> 
> What several people *did* say at this meeting was whether you could
> drop the anon stuff for now until we have consensus.

My read on the meeting was that most of people had nothing against anon
stuff, but asked if Willy could drop anon parts to get past your
objections to move forward.

You was the only person who was vocal against including anon pars. (Hugh
nodded to some of your points, but I don't really know his position on
folios in general and anon stuff in particular).

For record: I think folios has to be applied, including anon bits. They
are useful and address long standing issues with compound pages. Any
future type-safety work can be done on top of it.

I know it's not democracy and we don't count votes here, but we are
dragging it for months and don't get closer to consensus. At some point
"disagree and commit" has to be considered.

-- 
 Kirill A. Shutemov