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[173.79.60.52]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-52db612c2bfsm1249061cf.11.2026.08.16.17.46.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 16 Aug 2026 17:46:19 -0700 (PDT) Date: Sun, 16 Aug 2026 20:46:16 -0400 From: Gregory Price To: Rakie Kim Cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-cxl@vger.kernel.org, nvdimm@lists.linux.dev, ziy@nvidia.com, matthew.brost@intel.com, joshua.hahnjy@gmail.com, byungchul@sk.com, ying.huang@linux.alibaba.com, apopple@nvidia.com, david@kernel.org, ljs@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, dave@stgolabs.net, jic23@kernel.org, dave.jiang@intel.com, alison.schofield@intel.com, vishal.l.verma@intel.com, ira.weiny@intel.com, harry@kernel.org, kernel_team@skhynix.com, honggyu.kim@sk.com, yunjeong.mun@sk.com Subject: Re: [PATCH 0/4] mm/mempolicy: introduce package-aware weighted interleave Message-ID: References: <20260813062351.1856-1-rakie.kim@sk.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: <20260813062351.1856-1-rakie.kim@sk.com> On Thu, Aug 13, 2026 at 03:23:48PM +0900, Rakie Kim wrote: > On Wed, 12 Aug 2026 22:37:06 -0400 Gregory Price wrote: > > The cpuset.mems = 0,2 you describe is the node set of package 0, so > the tasks in that cgroup use node0 and node2 wherever they run. > I think you are over-complicating the explanation and that's making it hard for folks to reason about this. My best understanding here is for multi-socket systems, weighted interleave as-designed is inherently sub-optimal for scaled workloads that utilize multi-socket ("package") memory resources (DRAM, CXL...) I think there is also an assumption that total memory utilization is less than the total capacity - otherwise some of the assumptions here break, but that comes with the general weighted interleave story. I'm getting back from vacation, I will take a closer look this week. ~Gregory