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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.3 (3.54.3-2.fc41) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Fri, 2025-11-21 at 17:52 -0800, Chris Li wrote: > On Fri, Nov 21, 2025 at 3:40=E2=80=AFAM Johannes Weiner > wrote: > >=20 > >=20 > > Zswap is primarily a compressed cache for real swap on secondary > > storage. It's indeed quite important that entries currently in > > zswap > > don't occupy disk slots; but for a solution to this to be > > acceptable, > > it has to work with the primary usecase and support disk writeback. >=20 > Well, my plan is to support the writeback via swap.tiers. >=20 How would you do writeback from a zswap entry in a ghost swapfile, to a real disk swap backend? That is the use case people are trying to solve. How would your architecture address it? --=20 All Rights Reversed.