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b=UPfFCCBOQrCyjuhtIU81C7x3UyxX/24ttDZ7zGx377z73lyiTsCPdcPhzZRXrt43j vDKGnS31T+/GRX7W8F7gcTkVZG5udXjJ8fXTunnp9EX9mT2pm3FGwUjvlU/23A8S3h W1cwQpa3CKcPL83SbV8IiJkOWtSMkoUSO/AnMJkYSdK/4bS6Wx5vPsCT4U+eFK75lc wBsTEdpKWZGW5SdTk7nCkbIM5utUfSZIMKNH8+0+a180Y7KxNmy3TPoUGM4Nk8GZYT qJyITddIu5c+c13RFS/EfptQcHNMgEl56OStwNZPTVajvjR+/JtUVCf8n/uxc6iMil DPKNH45PQPZ9g== From: SJ Park To: Bharata B Rao Cc: SJ Park , Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Jonathan.Cameron@huawei.com, dave.hansen@intel.com, gourry@gourry.net, mgorman@techsingularity.net, mingo@redhat.com, peterz@infradead.org, raghavendra.kt@amd.com, riel@surriel.com, rientjes@google.com, weixugc@google.com, willy@infradead.org, ying.huang@linux.alibaba.com, ziy@nvidia.com, dave@stgolabs.net, nifan.cxl@gmail.com, xuezhengchu@huawei.com, yiannis@zptcorp.com, david@kernel.org, byungchul@sk.com, kinseyho@google.com, joshua.hahnjy@gmail.com, yuanchu@google.com, balbirs@nvidia.com, alok.rathore@samsung.com, shivankg@amd.com, donettom@linux.ibm.com Subject: Re: [PATCH v8 0/8] mm: Hot page tracking and promotion infrastructure Date: Thu, 6 Aug 2026 06:44:53 -0700 Message-ID: <20260806134454.96428-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: A73EA100006 X-Stat-Signature: dq31t5896amqnb9ofuq6ibrawbtyduip X-HE-Tag: 1786023904-404671 X-HE-Meta: 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 6rWYtvIW C4MCOP5G4zc5vJgF21ZAhhCPCRrbxvfqcXpbe/IcucjE7sDlsDZrXMjM5vKGhIsYps0eHRkdFotExyr9tbjupcfiRK2Me9Ttpbu0Z1Embohr4GX+4Ti3K4uAjx2VdzjpcTaYmHF9aRZrrrsSkH7m7D8r/1axqTp3Gf7byrcv/qm9fQ7SJHhZ/rEKD0bxQ74bdrLY2t9EH7lm2yMS824QdE86Af/9Zt8ZGl47YKZ9rXtL2MXvd7a7KNRIKWBNfvytLhiRXQh5SuMX28kDzKdRxXde4a1/RD5wABj9BYu8XEOCRPER9EyczhCjgFg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, 6 Aug 2026 11:19:22 +0530 Bharata B Rao wrote: > On 28-Jul-26 11:44 PM, Andrew Morton wrote: > > On Tue, 28 Jul 2026 11:13:48 +0530 Bharata B Rao wrote: > > > >> This patchset introduces pghot, a subsystem for hot page tracking and > >> promotion. > > > > Can DAMON be used to do this sort of thing adequately? > > Hi SJ, > > I started comparing hot page detection and promotion aspects of DAMON > and pghot through benchmark runs. Here is the first set of results from > pointer chase workload. > > Since I wasn't very familiar with DAMON tunables and settings, I let the > AI to chose some default followed by other combinations. The test harness > is developed and run by AI. Request you to go through this and let me know > you feedback about the combinations and configurations tried here. Based on > that I can adapt the settings for the future runs. This sounds like you asked AI to do the comparison because you don't know DAMON. And you still don't know DAMON, so you cannot really explain the results. So asking me to review what your AI did and guide your AI. Sigh. Correct me if I'm wrong. If I'm not wrong, no, I'm not an AI slop reviewer. I will not review that until this is clarified. I call it AI slop regardless of the output when it is something that generated and shared without full understanding from the human user. If you want me to review something, please send me what you really understand. To compare/discuss DAMON, please learn it first. Spend time and ask question. I will be more than happy to help that. Thanks, SJ [...]