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b=G0CBnfR+r8GsYvMtK51cAQ4P0lYZCQiXV1lzOfbpdd4vGoScucXAEDHGFQ+NA5KS/ gdngN9jzOv1nACTI3xltpWDcGgkCKOfxd5PmJEAjNehGMSatJXb12KIv1lh8pLBqdz 19QQXFViYyfy6g74JXyx+Vo/wrrlTZ+W8k3gTjd0= Date: Fri, 7 Feb 2025 18:20:09 -0800 From: Andrew Morton To: Joshua Hahn Cc: gourry@gourry.net, hyeonggon.yoo@sk.com, ying.huang@linux.alibaba.com, honggyu.kim@sk.com, rafael@kernel.org, lenb@kernel.org, gregkh@linuxfoundation.org, rakie.kim@sk.com, dan.j.williams@intel.com, Jonathan.Cameron@huawei.com, dave.jiang@intel.com, horen.chuang@linux.dev, hannes@cmpxchg.org, linux-kernel@vger.org, linux-acpi@vger.kernel.org, linux-mm@kvack.org, kernel-team@meta.com Subject: Re: [PATCH v5] mm/mempolicy: Weighted Interleave Auto-tuning Message-Id: <20250207182009.7fc099c3074ad00338f25e0a@linux-foundation.org> In-Reply-To: <20250207201335.2105488-1-joshua.hahnjy@gmail.com> References: <20250207201335.2105488-1-joshua.hahnjy@gmail.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Queue-Id: 282FA40006 X-Stat-Signature: 6ywnx8qihxcqg3wkdmfn79fadh4sw6fm X-Rspamd-Server: rspam03 X-HE-Tag: 1738981211-333442 X-HE-Meta: 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 8fy/Eelg bJvubSQL4m4DpOpCKBjRwJk0CVLH8qcymFb+Wxs7CJ+4+bwcbWBuzV1g8OHCMxFo3pSvxCKZGJfQPvIlyYn3rajle5NJ0tSiZKeAw6n4OKGsgm9+5SJM5UvaVRCxKlvhpNgJuf3DTu/eYsunoS3bgqftg76XSyzLjX5YzB/l/T8eZcEmRF/UicHImbmkruvgqfMNYRW1ABtrCbGwR5oBoEi/OSpTTXhetDMOqCRKly9DSOsAZ4Szu8vZli6ApwCjo0Eo0IfziQblW+55KWtPqpx/bdMCl8UoSidrJEzSCiSUFVL3oRN0fOmGsZgCsuHW8f0eMLibJ/HGqWOkBsiKLHyyv6g== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, 7 Feb 2025 12:13:35 -0800 Joshua Hahn wrote: > This patch introduces an auto-configuration mode for the interleave > weights that aims to balance the two goals of setting node weights to be > proportional to their bandwidths and keeping the weight values low. > In order to perform the weight re-scaling, we use an internal > "weightiness" value (fixed to 32) that defines interleave aggression. Question please. How does one determine whether a particular configuration is working well? To determine whether manual-configuration-A is better than manual-configuration-B is better than auto-configuration? Leading to... how do we know that this patch makes the kernel better?