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[58.152.75.21]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-35a02fc9454sm7295623a91.12.2026.03.12.20.39.43 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 12 Mar 2026 20:39:46 -0700 (PDT) Message-ID: <06535c30-ce87-43b2-9670-53e56ca04c3c@gmail.com> Date: Fri, 13 Mar 2026 11:39:41 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] mm/mempolicy: add sysfs interface to override NUMA node bandwidth To: Joshua Hahn Cc: akpm@linux-foundation.org, david@kernel.org, dan.j.williams@intel.com, ying.huang@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Jonathan.Cameron@huawei.com, linux-cxl@vger.kernel.org, dave.jiang@intel.com, gourry@gourry.next References: <20260312150022.1373486-1-joshua.hahnjy@gmail.com> Content-Language: en-US From: Yee Li In-Reply-To: <20260312150022.1373486-1-joshua.hahnjy@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 84372C0002 X-Stat-Signature: f68gik77goiwm8rcmy57qn6bxb1wzreq X-HE-Tag: 1773373188-99540 X-HE-Meta: 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 il2lF2DY 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hi Joshua, Thanks for your feedback and kind wishes. > I just wanted to touch on this. Is this true? Weighted interleave already > exposes sysfs that lets the user set the weights they want. On one hand > I think it would be helpful for there to be a tool to see what the > effects of setting bandwidth information on a system could be, if it > had other side effects. I'm not sure if there is a strong case to do this > purely for weighted interleave auto-tuning, which already has a manual > weight override and pretty simple calculations : -) I agree — writing a small userspace tool to compute the weights based on actual measured bandwidths (from mlc or stream) is a really good approach. > Thank you for the helpful clarification. Just to be sure, are there > other intended things that the user can test other than what weights > weighted interleave would resolve to? We can continue DRAM + CXL weighted interleave performance testing later, following Gregory Price's experiments [1]. [1] Link: https://lore.kernel.org/linux-mm/20240103224209.2541-1-gregory.price@memverge.com/