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Fri, 25 Sep 2026 05:44:13 +0000 X-Mizu-Trace-ID: 14310745666562df X-Migadu-Flow: FLOW_OUT From: Lance Yang To: sj@kernel.org, mst@redhat.com, david@kernel.org Cc: damon@lists.linux.dev, linux-mm@kvack.org, virtualization@lists.linux.dev, ryncsn@gmail.com, kunwu.chan@gmail.com, lianux.mm@gmail.com, baohua@kernel.org, xueyuan.chen21@gmail.com, Lance Yang Subject: [FYI] DAMON and virtio-balloon in DeepSeek's DSec paper Date: Fri, 25 Sep 2026 13:44:08 +0800 Message-ID: <20260925054408.10431-1-lance.yang@linux.dev> X-Mailer: git-send-email 2.49.0 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: AE4EC100003 X-Stat-Signature: qsyj8bigtgbbrz853fbfaqzo4y7hjng8 X-HE-Tag: 1790315055-474438 X-HE-Meta: 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 aTSO9Nve s1qXXnL+9aguPxQrxinAgllYo+wDQl9NzXhLpPqlayB1enmTjDyOERpx1s6AIHMFV3pyOMgG8zmC5tQ2HF/YfNIqHUy50bVZuF33e229iYzim10KxjmKQM2psSQpsVXsbW0m/wB/ec2mJHyBk6Qr/aZ7DW6u7UWL6dd+4T/ETW7f19lfKvDAeRXdSjqpVJgRe7VGjz37VQO0U2hWnWqb4SWE7xcyjWM7MUD5FfCCBMW1OuzNjfa67in0cDDMrZASkcTlbXjpZ/985VsJiCuVs9ECUmqNzyvlWTiMXLIq/376QqJYhgrBZmFiHm3aUehfAA6BQTBo3bGkWdxM= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hi all, I was reading DeepSeek's new DSec paper[1] and found a nice use of DAMON and virtio-balloon: With this kind of workload, an agent may read a file once and never touch it again, while those pages remain in the guest page cache. Without memory pressure in the guest, they can stay cached even though the host would like that memory back ... The trick is DAMON + virtio-balloon free-page reporting :) DAMON reclaims cold file pages from the guest page cache; buddy gets a chance to coalesce them into reportable blocks, and virtio-balloon passes those blocks to Firecracker. Firecracker can then drop the host backing with MADV_DONTNEED. And it worked: time-integrated host memory use fell by 21.2%, while peak usage stayed about the same, with no significant CPU overhead. Pretty cool to see these pieces show up in another real, large-scale system :) Kernel work still changes the world. Cheers to that! Anyhow, I still don't know DAMON and virtio-balloon as well as I should (mostly I just know the people who built them) :P [1] https://arxiv.org/html/2609.22978 Cheers, Lance