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[96.255.20.138]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-87cf5235384sm91023196d6.28.2025.10.22.08.05.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 Oct 2025 08:05:19 -0700 (PDT) Date: Wed, 22 Oct 2025 11:05:16 -0400 From: Gregory Price To: Jonathan Cameron Cc: hannes@cmpxchg.org, Yiannis Nikolakopoulos , Wei Xu , David Rientjes , Matthew Wilcox , Bharata B Rao , linux-kernel@vger.kernel.org, linux-mm@kvack.org, dave.hansen@intel.com, mgorman@techsingularity.net, mingo@redhat.com, peterz@infradead.org, raghavendra.kt@amd.com, riel@surriel.com, sj@kernel.org, ying.huang@linux.alibaba.com, ziy@nvidia.com, dave@stgolabs.net, nifan.cxl@gmail.com, xuezhengchu@huawei.com, akpm@linux-foundation.org, david@redhat.com, byungchul@sk.com, kinseyho@google.com, joshua.hahnjy@gmail.com, yuanchu@google.com, balbirs@nvidia.com, alok.rathore@samsung.com, yiannis@zptcorp.com, Adam Manzanares Subject: Re: [RFC PATCH v2 0/8] mm: Hot page tracking and promotion infrastructure Message-ID: References: <20251017153613.00004940@huawei.com> <20251020150526.000078b6@huawei.com> <20251022100950.00002785@huawei.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: <20251022100950.00002785@huawei.com> On Wed, Oct 22, 2025 at 10:09:50AM +0100, Jonathan Cameron wrote: > > My gut feeling is the need to do dynamic NUMA nodes will not be driven > but this but more by large scale fabrics (if that ever happens) > and trade offs of host PA space vs QoS in the hardware. Those > trade offs might put memory with very different performance > characteristics behind one window. > I can't believe we live in a world where "We have to think about the scenario where we actually need all 256 TB of 48-bit phys-addressing" is not a tongue in cheek joke o_o That's a paltry 2048 128GB DIMMs... and whatever monstrosity you have to build to host it all but that's at least a fun engineering problem :V Bring on the 128-bit CPUs! What do we name those x86 registers though? Slap the E back on for ERAX? > Meh. Let's suggest people burn host PA space for now. If anyone hits > that limit they can solve it (crosses fingers it's not my lot :) > +1 ~Gregory