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charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Rspamd-Queue-Id: BAE1C4000A X-Stat-Signature: nm9dfae4fqmff9ibib36xeeohzgn5dfg X-Rspam-User: X-Rspamd-Server: rspam12 X-HE-Tag: 1783958258-469121 X-HE-Meta: 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 xZCE+AFW hrnOiGsEdwXBk6kFjdKBmOUfp7e/siwI+U4VaWQbi5cIC8EipfPKVxSLLGcyR0UzniGhb98NDbWycNedXUJANQUUhzRRAIx1GstGF+XXiowlXsjRDqN/bKEddMFJ/eVdGDeBlNOaXvvlQE86CwV8oOZPVSRt77BIn8KAv7Sp3kmp/BoZwHkakmR6LGTUnxstweaBIgzgKiovJ3V+sjr4jJ+DFW+HAAhAYL44y0QdqiIhHxp3PRTIRYrUARrL7i8TTLyF8RL/AQy1MXlEDzWBVX/fw5605fRPemOAo8LLtkqVNavY5wCQ1efVYnQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Jul 13, 2026 at 08:50:36AM -0700, Yosry Ahmed wrote: > On Sun, Jul 12, 2026 at 7:57 PM Youngjun Park wrote: > > > > This is the v10 series of the swap tier patchset. > > > > v10 folds in the Sashiko review fixes for the selftests added in v9 and > > rebases onto the current mm-new. There are no functional changes to the > > core swap or memcg code since v9; see the changelog for details. > > > > For context, the bulk of the series is unchanged since v8, with great thanks > > to Shakeel Butt and Yosry for the reviews and discussions [1] that shaped it. > > The main change in v8 was the interface change to use memory.swap.tiers.max > > with '0' (disable) and 'max' (enable) values. This mechanism was suggested > > by Shakeel and Yosry. > > > > This change allows for future extensions to control swap between tiers and > > aligns better with existing memcg interfaces. It is confined to patch #3's > > user-facing interface; internally, patch #3 still uses the existing mask > > processing method, which is implementation-efficient. > > > > We also discussed tier extensions. Thanks to Yosry, Nhat and Shakeel for their > > valuable feedback. > > > > Here is a brief summary of our tentative conclusions. Please correct me > > if anything is misrepresented (details in references): > > > > * Zswap tiering [2]: > > Zswap can itself be a tier (typically the fastest one). But, until vswap lands, > > zswap cannot be the only allowed tier, > > since it still needs a physical device for allocation; > > that restriction can be lifted once vswap is supported. > > Does this series support zswap being a tier? I cannot find any mention > of zswap in the patches. Hello Yosry! This series does not cover zswap as a tier yet. My plan is to land the swap tier infrastructure together with the first use case (cgroup-based swap control) first, and then follow up with zswap tier support in a subsequent series, continuing the discussions we've had above. (I mentioned on cover letter, right above the overview section) Does that approach sound reasonable to you?