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charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Rspamd-Server: rspam11 X-Stat-Signature: r5mw1u48azta6owmzaw8yhf5x1mbejea X-Rspam-User: X-Rspamd-Queue-Id: D42DB140006 X-HE-Tag: 1770947984-342966 X-HE-Meta: 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 G2J0w9g6 LfozBpOV1q69siGBLA0XZo8ZIqkNAtkyj8FJs2nDy0zns53zI9wdgaBiiHmayoqHAAVZxNG8siD71jIMlrqIMu2YCq/IfpwHaGsFJcxSiMd1QlmHYkM16w5loNzm3Ruw+kyCRais7DA3shRH77WwNDIOYKyp8GHV8G0oFhPZRywt2T7f4U7Fd4xIC6VcffGvijFy0VSiBi4e6qP2jIw91k6jCWerR4tUw3ovNOVgKRaqAPwVqC3XRoNY0GE+Y9oPVSAkbO+B+xols321/lTeo590kfIrQ4V5s43Iw 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 Wed, Feb 11, 2026 at 10:12:04PM -0800, Chris Li wrote: > Hi Youngjun, > > On Sun, Jan 25, 2026 at 10:53 PM Youngjun Park wrote: > > > > This is the second version of the RFC for the "Swap Tiers" concept. > > Link to v1: https://lore.kernel.org/linux-mm/20251109124947.1101520-1-youngjun.park@lge.com/ > > > > This version incorporates feedback received during LPC 2025 and addresses > > comments from the previous review. We have also included experimental > > results based on usage scenarios intended for our internal platforms. > > Thanks for the patches series. > > Sorry for the late reply. I have been wanting to reply to it but get > super busy at work. > > Some high level feedback for the series. Now that you demonstrated the > whole series, let's focus on making small mergiable baby steps. Just > like the swap table has different phases. Make each step minimal, each > step shows some value. Do the MVP, we can always add more features as > a follow up step. > > I suggest the first step is getting the tiers bits defined. Add only, > no delete. Get that reviewed and merged, then the next step is to use > those tiers. > > Chris Hi Chris, Thank you for the direction. I agree that breaking the series into smaller, mergeable steps is the right approach. However, since introducing the definitions alone might lack immediate usage, I propose a slightly modified roadmap to ensure Step 1 demonstrates some value. Here is the plan I have in mind. 1. Swap Tier Definition & Addition - Introduce the concept, grouping logic, and the 'add' interface. - Value: Enables basic exception handling within the swap device itself using tiers. 2. Advanced Control (Delete/Modify) - Implement logic to remove or update tiers. - Value: Enhances the usability and management of the tiers established in Step 1. 3. External Integration (memcg, bpf etc ... ) - Apply swap tiers for broader swap control. - Value: Connects swap tiers to other subsystems like memcg. Does this roadmap look reasonable to you? I will proceed with preparing the real patch series based on this structure. Best regards, Youngjun