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Wed, 06 May 2026 08:22:40 -0700 (PDT) Date: Wed, 6 May 2026 16:22:34 +0100 From: Gregory Price To: Matthew Wilcox Cc: Bharata B Rao , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Jonathan.Cameron@huawei.com, dave.hansen@intel.com, 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, akpm@linux-foundation.org, 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 v7 0/7] mm: Hot page tracking and promotion infrastructure Message-ID: References: <20260504060924.344313-1-bharata@amd.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, May 04, 2026 at 09:36:05PM +0100, Matthew Wilcox wrote: > On Mon, May 04, 2026 at 11:39:17AM +0530, Bharata B Rao wrote: > > This is v7 of pghot, a hot-page tracking and promotion subsystem. The > > I continue to think we should not do this. My only pushback on the general "we should not do this" is that we need something to counter-balance the demotion bit in vmscan.c, and the current implementation (prot_none faults) is rather :[ I think this series needs to greatly limit its complexity and provide some gentle correction for LRU inversions, and I think they're making a decent attempt at that. But then I think local memory expansion on CXL is going pretty swimmingly in our datacenters :], others may not feel the same. ~Gregory