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Howlett" , Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , Bjorn Roy Baron , Benno Lossin , Andreas Hindborg , Trevor Gross , Yosry Ahmed , Nhat Pham , linux-mm@kvack.org Content-Transfer-Encoding: quoted-printable Message-Id: References: <20250823130420.867133-1-vitaly.wool@konsulko.se> <20250826124454.GA1502@cmpxchg.org> To: Johannes Weiner X-Mailer: Apple Mail (2.3696.120.41.1.1) X-Rspamd-Queue-Id: 35D351C0006 X-Stat-Signature: 3krarhzjwm43exi3g9osuc1cg5dunpg4 X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1756220214-256483 X-HE-Meta: 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 5a8l/pIV uQvQVLBKbZnW0sZCs/GlZryutwpxYFyyGxFCsOiihrHLtOyEiRhdTNiQ2d4YFtrDXIyhTx1XvzT1pjmF1ZX9ikp5NoOInmGS4cghOewJbJKXPJA4EmibVfQXZwZh+qDmOxbTa/lmhOvv4tEkMgWS4g4iicbzKKh/psWgVx1kBPFKc4gQReHztnoAZf6HFG8Azbs+7AVOvJBOuOpOf7401BHOj/AlKAJ8esJu1keauSu/TEpzBadL2gk14srK+0eWl+XJpNigGtWip/nYY3H1bRxrTGnc4evC3lLtRup5F/YlCpwarjFeAfCsqeg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > On Aug 26, 2025, at 2:44 PM, Johannes Weiner = wrote: >=20 > On Sat, Aug 23, 2025 at 03:04:19PM +0200, Vitaly Wool wrote: >> Zpool is a common frontend for memory storage pool implementations. >> These pools are typically used to store compressed memory objects, >> e. g. for Zswap, the lightweight compressed cache for swap pages. >>=20 >> This patch provides the interface to use Zpool in Rust kernel code, >> thus enabling Rust implementations of Zpool allocators for Zswap. >=20 > The zpool indirection is on its way out. >=20 > When you submitted an alternate allocator backend recently, the > resounding feedback from the zswap maintainers was that improvements > should happen to zsmalloc incrementally. It is a lot of code and has a > lot of features that go beyond allocation strategy. We do not want to > fork it and fragment this space again with niche, incomplete backends. >=20 > It's frustrating that you not only ignored this, but then went ahead > and made other people invest their time and effort into this as well. >=20 I don=E2=80=99t think we have a consensus on that. And zblock is, after some additional improvements, just better than = zsmalloc in all meaningful aspects, let alone the simplicity. It is fas = easier to implement in Rust than zsmalloc, too. Besides, zram is a good = candidate to be rewritten in Rust as well and after that is done, zblock = will be even safer and faster. So while not being =E2=80=9Cincomplete", = it=E2=80=99s zsmalloc that is becoming a niche backend moving forward, = and I would argue that it could make more sense to eventually obsolete = *it* rather than the zpool API. ~Vitaly=