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 9282D20125F; Tue, 18 Aug 2026 06:01:38 +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=1787032903; cv=none; b=PcL1H/UxGfhOwVLH23R7lilKRLhhwiGTr/2jrCO+jdo3H1b/5gya/CXXHwOtiHuv4D/UKGNbhQpPQipI/m+CnjTEuFE5vgJfFZdzwZmlRYbFZmZMo5MBGDQ+gZJ4gyNbAhQiYFLT+mfBG2eT1Uj4LUk//i0wI5IOalSi1Wxie80= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787032903; c=relaxed/simple; bh=2HWQ+1Hofy0TiNJM3gg9vufAVBmsJX2uYq+bDtHscK8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SHdyn0EYStQYHiL8XS2Q9OU0zNg17nPXMTzae/eVe0f0WhKVp4RVzu3L3/kS58NTIaQ87mBYINRRjw+QVG7aTcOHLNr1sAcNxJpyUEIidIrlU1j2+aao1Oit0le8VqNz85NKJhJUWcLYJItRRLUy/KNULetjsHpWoD2ssbY5rd8= 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-c45ff70000001609-84-6a83f53a1e00 From: Rakie Kim To: Gregory Price 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, Rakie Kim Subject: Re: [PATCH 0/4] mm/mempolicy: introduce package-aware weighted interleave Date: Tue, 18 Aug 2026 15:01:25 +0900 Message-ID: <20260818060128.1876-1-rakie.kim@sk.com> X-Mailer: git-send-email 2.52.0.windows.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrFIsWRmVeSWpSXmKPExsXC9ZZnka7V1+Ysg7svTCzmrF/DZnH38QU2 i103QixO3Gxks1h9cw2jxfOtvxgtft49zm5x/dZKRov9T5+zWDxoWsVkcXzrPHaLdacOsVmc n3WKxeLyrjlsFvfW/Ge1ePPYzeJbn7TF/T4Hi5U//rBaHFm/ncli8qUFbBYdL++zWNyacIzJ YvWaDIvZR++xO0h67Jx1l91jwaZSj+62y+wem1doeSze85LJY9OqTjaPTZ8msXucmPGbxWPn Q0uPF5tnMnr0Nr9j85g6u95j/ZarLB6fN8kF8EVx2aSk5mSWpRbp2yVwZayYNpm94BRnxdbV vewNjNfYuxg5OCQETCTObo3uYuQEM48u38cEEmYTUJI4tjcGxBQRUJVou+IOUsEssI1V4tZF TRBbWCBIomv6c0YQmwWo5Nny2Ywg5bxAU9raRSEGakqs23iLBcTmFDCTuPTgOhuILSTAI/Fq w36wVl4BQYmTM5+wQIyXl2jeOpu5i5ELqPcru8T7qV/ZIAZJShxccYNlAiP/LCQ9s5D0LGBk WsUolJlXlpuYmWOil1GZl1mhl5yfu4kRGKPLav9E72D8dCH4EKMAB6MSD++OD01ZQqyJZcWV uYcYJTiYlUR4P04GCvGmJFZWpRblxxeV5qQWH2KU5mBREuc1+laeIiSQnliSmp2aWpBaBJNl 4uCUamBMeF7oMPnf3KKPCsuZj37dvCTl6J9lQuVc1xb0RK2OlhTXaJ23beY7Uc8dZ7iMxGzF nwvVfo/Xdp3lJyTH/aI00tzkfd/N/b9lT2SeXHX83HRWs+pJjz8GrjjSU1O1x2qz4gEmz3cG OiKWXo7LTYU5Xhn8Va4MuL97n0eSisrHoqbrwg0vK24qsRRnJBpqMRcVJwIACE9UAM0CAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrFIsWRmVeSWpSXmKPExsXCNUM9Rtfqa3OWwa+HmhZz1q9hs7j7+AKb xa4bIRbnpsxmszhxs5HNYvXNNYwWz7f+YrT4efc4u8X1WysZLT4/e81ssf/pcxaLB02rmCyO b53HbnF47klWi3WnDrFZnJ91isXi8q45bBb31vxntXjz2M3iW5+0xf0+B4uVP/6wWhy69pzV 4sj67UwWky8tYLPoeHmfxeLWhGNMFqvXZFj83raCzWL20XvsDnIeO2fdZfdYsKnUo7vtMrvH 5hVaHov3vGTy2LSqk81j06dJ7B4nZvxm8dj50NLjxeaZjB69ze/YPL7d9vBY/OIDk8fU2fUe 67dcZfH4vEkuQCCKyyYlNSezLLVI3y6BK2PFtMnsBac4K7au7mVvYLzG3sXIySEhYCJxdPk+ pi5GDg42ASWJY3tjQEwRAVWJtivuIBXMAttYJW5d1ASxhQWCJLqmP2cEsVmASp4tn80IUs4L NKWtXRRioKbEuo23WEBsTgEziUsPrrOB2EICPBKvNuwHa+UVEJQ4OfMJC8R4eYnmrbOZJzDy zEKSmoUktYCRaRWjSGZeWW5iZo6pXnF2RmVeZoVecn7uJkZgjC6r/TNxB+OXy+6HGAU4GJV4 eHd8aMoSYk0sK67MPcQowcGsJML7cTJQiDclsbIqtSg/vqg0J7X4EKM0B4uSOK9XeGqCkEB6 YklqdmpqQWoRTJaJg1OqgdFl/qbSS7d3Z2ccnMN56dGi5qMNUyWDVZqXLajcd27/Fx6BFXlJ T+8znPnGIiw6d5r0XNar6u6yM/r+Rq14uqRhI7O3D9fjs55KW49w2OQ7/7vRWnTBNztAaIF0 e/aK83zTCjblpJaaXjwh8Ud7dtEF49bixnPl6rk9QV/k34WtEfKZ97nd7pASS3FGoqEWc1Fx IgCfDHa9zQIAAA== X-CFilter-Loop: Reflected On Sun, 16 Aug 2026 20:46:16 -0400 Gregory Price wrote: Hello Gregory, Thanks for your review and feedback. > I think you are over-complicating the explanation and that's making it > hard for folks to reason about this. You are right. I will keep my explanations focused on the key points from here on, and the next cover letter will be written that way as well. > 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...) Your summary is correct. That is the problem this series addresses. > 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. Your assumption is correct. It is the same as the existing weighted interleave: when the nodes are full, memory is allocated from other nodes. > I'm getting back from vacation, I will take a closer look this week. Thank you. I look forward to your comments. Thanks again for your time and review. Rakie Kim