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Received: from willy by casper.infradead.org with local (Exim 4.99.1 #2 (Red Hat Linux)) id 1womTu-0000000DxDa-0uJx; Tue, 28 Jul 2026 18:24:46 +0000 Date: Tue, 28 Jul 2026 19:24:46 +0100 From: Matthew Wilcox To: Andrew Morton Cc: Bharata B Rao , 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, sj@kernel.org, weixugc@google.com, 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 Message-ID: References: <20260728054356.291998-1-bharata@amd.com> <20260728111401.b6d674baf8e56a27c55e0c52@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260728111401.b6d674baf8e56a27c55e0c52@linux-foundation.org> X-Rspam-User: X-Rspamd-Queue-Id: CBC941C0011 X-Rspamd-Server: rspam01 X-Stat-Signature: 4cyca3hfj9o1ixe4uot451y561yw7qad X-HE-Tag: 1785263094-862188 X-HE-Meta: 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 g8q3Pi4+ U1Ki1efYaVHAnW50b2W5HiIv7ztLpVkNJVslXHRu4A0cEAAxfsBsV7JUXIolu6OStsFALElejfyBM4E9z6R6oUq/nlteTW7MLL+/zMA733q+KLGNjKKODfSPPgmjqA7A04hsxWr6r78URgnz5hvHydJ9dsRY0i6FlamAIsP4b07RvyYYBjgD4GQbR+HAB4nhXnNGsiH+QGMK63yImEaweUICvNHGhvOiyXpG2lML4qMoCix9AIvV+pHMLErm6BWH2My2VKcQmeBVVMZDCP+pf5k9jbk2BAxKOSWl3jFg7dVIsQ1Rpf1pZ46iQSOC0ReJPaQygbnoRYO5Rn+uapEDf4ZOqJw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Jul 28, 2026 at 11:14:01AM -0700, 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? > > Thanks, I'll await review input on this. I don't think we should do this. I don't think it's a use-case that customers actually want; I think it's something CPU vendors think their customers want. I've said this repeatedly over the months this patchset has been in development. I say no.