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Mon, 20 Jul 2026 18:34:39 -0700 (PDT) From: Lian Wang To: sj@kernel.org, david@kernel.org, ziy@nvidia.com Cc: damon@lists.linux.dev, linux-mm@kvack.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, ljs@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, npache@redhat.com, baolin.wang@linux.alibaba.com, ryan.roberts@arm.com, daichaobing@sangfor.com.cn, wangkefeng.wang@huawei.com, gutierrez.asier@huawei-partners.com, zengheng4@huawei.com, kasong@tencent.com, corbet@lwn.net, skhan@linuxfoundation.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, lianux.mm@gmail.com, lianux.wang@processmission.com, kunwu.chan@linux.dev Subject: Re: [RFC PATCH v3 0/3] mm/damon: introduce DAMOS_SPLIT action Date: Tue, 21 Jul 2026 09:34:30 +0800 Message-ID: <20260721013430.40303-1-lianux.mm@gmail.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721004755.93824-1-sj@kernel.org> References: <20260721004755.93824-1-sj@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi SJ, On 7/20/2026 5:47 PM, SJ Park wrote: > To me, it's still unclear what is the real user impact, though. > ... > Only after understanding what is the problem and how bad it is, we > will be able to think of different approaches and assess those. You are right. I will work with Sangfor to quantify the real impact in their production scenario -- what DAMOS action is driven by the inflated hot-memory readings, and how badly the monitoring error affects the actual outcome. Thank you, David, and Zi Yan for the honest and constructive feedback. It made me realize I should have led with the problem, not the mechanism. Let me take a step back, gather concrete data on the problem severity, and come back with a clearer picture. I will follow up in this thread once I have something solid to share. Thanks, Lian Wang