From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from invmail4.hynix.com (exvmail4.skhynix.com [166.125.252.92]) by smtp.subspace.kernel.org (Postfix) with ESMTP id B545020125F; Tue, 18 Aug 2026 06:01:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=166.125.252.92 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787032910; cv=none; b=a3OVer1dtSkBBudyjjqE2QdMHKnVO6FP9epzPRFOZd5UfDntxjhLOfaZrRM+YCdmmp44xrS0vqiCzx5pvhPUKa+QvDHIpzaNsBvDKgTM9dLYua1RLJI61QYxsKCOoa/bUTbRXVemykn4dygnw4JrnYRNAvzOvD0w+x7gP5OQ0jE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787032910; c=relaxed/simple; bh=HgewIRpkemtGNOuhpM62yzSblJpWdOMvsCDjbtIDozc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=X86x1UKX7Kc9wMC7et8U9860w+Fu39jDRY7jKo4z9TLzPozOT5KzigR3cByWb9e53HAp4g8ohy3K/RZUFq3KLlr7h0ZIavFMBz1GqoFKdkDPnW5pB1tclhu3Eax71u75Yv530lXxnFCmGf9Mm8akMSmVDhKd5UppLIpgHisJIwM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sk.com; spf=pass smtp.mailfrom=sk.com; arc=none smtp.client-ip=166.125.252.92 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sk.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sk.com X-AuditID: a67dfc5b-c2dff70000001609-b0-6a83f54c0ffb From: Rakie Kim To: Joshua Hahn Cc: Rakie Kim , 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, 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, Gregory Price Subject: Re: [PATCH 0/4] mm/mempolicy: introduce package-aware weighted interleave Date: Tue, 18 Aug 2026 15:01:42 +0900 Message-ID: <20260818060145.1890-1-rakie.kim@sk.com> X-Mailer: git-send-email 2.52.0.windows.1 In-Reply-To: <20260817045225.1807518-1-joshua.hahnjy@gmail.com> References: Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrNIsWRmVeSWpSXmKPExsXC9ZZnka7P1+YsgzUtMhZz1q9hs7j7+AKb xa4bIRYnbjayWay+uYbR4vnWX4wWP+8eZ7e4fmslo8X+p89ZLB40rWKyOL51HrvFulOH2CzO zzrFYnF51xw2i3tr/rNavHnsZvGtT9rifp+Dxcoff1gtjqzfzmQx+dICNouOl/dZLG5NOMZk sXpNhsXso/fYHSQ9ds66y+6xYFOpR3fbZXaPzSu0PBbvecnksWlVJ5vHpk+T2D1OzPjN4rHz oaXHi80zGT16m9+xeUydXe+xfstVFo/Pm+QC+KK4bFJSczLLUov07RK4MpraTzMVTOet2Nou 1sC4jauLkYNDQsBE4s0JlS5GTjDz2Z/DbCBhNgEliWN7Y0DCIgKaEidaJzGD2MwCB1gldnbF gdjCAkESXdOfM4LYLAKqEv1fNoPV8AKNmbFgKiPESE2JdRtvsYDYnAL2Ek9PTGYCsYUEeCRe bdjPCFEvKHFy5hMWiPnyEs1bZwPN4QLq/cgucfjNZBaIQZISB1fcYJnAyD8LSc8sJD0LGJlW MQpl5pXlJmbmmOhlVOZlVugl5+duYgRG6bLaP9E7GD9dCD7EKMDBqMTDu+NDU5YQa2JZcWXu IUYJDmYlEd6Pk4FCvCmJlVWpRfnxRaU5qcWHGKU5WJTEeY2+lacICaQnlqRmp6YWpBbBZJk4 OKUaGB1szc0vrmxX8+Ovd5PW/HzNt7g2TVRrwgcPjqpLVqwqPaXvMvb7/r6e++N1XM4JXYub E/MLXdo2cNjICzfF1LRyHL3h8GvC9krBR+KeJfqhy9YK+vQdkf5TJbWg9vGkL27HnhVI3k9o V2uMqw6dvuZoVYxZ2LKzEwQmJRQ//SK+VljhycRrSizFGYmGWsxFxYkATuQ3sc4CAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrNIsWRmVeSWpSXmKPExsXCNUM9Rtfna3OWwdETvBZz1q9hs7j7+AKb xa4bIRbnpsxmszhxs5HNYvXNNYwWz7f+YrT4efc4u8X1WysZLT4/e81ssf/pcxaLB02rmCyO b53HbnF47klWi3WnDrFZnJ91isXi8q45bBb31vxntXjz2M3iW5+0xf0+B4uVP/6wWhy69pzV 4sj67UwWky8tYLPoeHmfxeLWhGNMFqvXZFj83raCzWL20XvsDnIeO2fdZfdYsKnUo7vtMrvH 5hVaHov3vGTy2LSqk81j06dJ7B4nZvxm8dj50NLjxeaZjB69ze/YPL7d9vBY/OIDk8fU2fUe 67dcZfH4vEkuQCCKyyYlNSezLLVI3y6BK6Op/TRTwXTeiq3tYg2M27i6GDk5JARMJJ79OczW xcjBwSagJHFsbwxIWERAU+JE6yRmEJtZ4ACrxM6uOBBbWCBIomv6c0YQm0VAVaL/y2awGl6g MTMWTGWEGKkpsW7jLRYQm1PAXuLpiclMILaQAI/Eqw37GSHqBSVOznzCAjFfXqJ562zmCYw8 s5CkZiFJLWBkWsUokplXlpuYmWOqV5ydUZmXWaGXnJ+7iREYpctq/0zcwfjlsvshRgEORiUe 3h0fmrKEWBPLiitzDzFKcDArifB+nAwU4k1JrKxKLcqPLyrNSS0+xCjNwaIkzusVnpogJJCe WJKanZpakFoEk2Xi4JRqYBRkNbLNOectwD5H+MJBh/U6i7z3We/0uJ30Y0Wo0+r0RxuUcwRy mzn/NPkfCF78xL7ZtnH3lubZ0yIWNn35wVx+N3R/TOb/Y8d+P9oboBfuw+qwtvFGh3ri5FqR BuHTk88Khuq+Vojpl/MNYLHXn3FIVSxQ/pXIDtkpxtsmzm4SiImS8Ji2UYmlOCPRUIu5qDgR AKUhhf7OAgAA X-CFilter-Loop: Reflected On Sun, 16 Aug 2026 21:52:24 -0700 Joshua Hahn wrote: Hello Joshua, Thanks for your feedback. > On Sun, 16 Aug 2026 20:46:16 -0400 Gregory Price wrote: > > > 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 was thinking about this and I think Gregory is right here. I agree. From now on I will keep my explanations focused on the key points. > I wonder how much of the framing around this series can be preserved / > simplified if we just say "prevent tasks from allocating memory > cross-socket". I think this is a good suggestion. Even if it is not this exact wording, I will look for a shorter and better description that includes your idea. > I also wonder if instead of limiting this to weighted interleave, > this can sit on top of other mpols and just nodemasks against > cross-socket nodes. It does not have to apply only to weighted interleave. Patch 2 simply groups NUMA nodes by the package they belong to. So the same grouping can also be used for interleave, not just weighted interleave. I have not applied it to interleave because I could not find a clear use case for it yet. > I am also out on vacation this week : -) > I'll take a closer look along with the code next week as well. Thank you. I look forward to your comments. Thanks again for your time and review. Rakie Kim