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s=arc-20220608; d=hostedemail.com; t=1738722370; a=rsa-sha256; cv=none; b=eo4V2ICpZcdtq/BRKrhbJrUPjKSWsmu0ymTUSmx13CKqIBSWncNQudtPwEkgOY1QE35ja7 mjsWWCozmPJsCpuhL66UahoWFZrC3KgwB0TbrMwhE71mtJzCMqGZXOv0HjnTPZhLGPSEyh 1tvIHhBFuOFhXR9XqCJ/NjFMXfG9I3k= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=none; spf=pass (imf01.hostedemail.com: domain of honggyu.kim@sk.com designates 166.125.252.92 as permitted sender) smtp.mailfrom=honggyu.kim@sk.com; dmarc=none X-AuditID: a67dfc5b-3c9ff7000001d7ae-4d-67a2cc3f7de9 Message-ID: <5b9a3776-8661-423a-853f-87fa8b9a7633@sk.com> Date: Wed, 5 Feb 2025 11:26:06 +0900 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: kernel_team@skhynix.com, Joshua Hahn , ying.huang@linux.alibaba.com, rafael@kernel.org, lenb@kernel.org, gregkh@linuxfoundation.org, akpm@linux-foundation.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.kernel.org, linux-acpi@vger.kernel.org, linux-mm@kvack.org, kernel-team@meta.com, 42.hyeyoo@gmail.com, Honggyu Kim Subject: Re: [PATCH v4] Weighted Interleave Auto-tuning Content-Language: ko To: Gregory Price References: <20250202141247.2219681-1-joshua.hahnjy@gmail.com> From: Honggyu Kim In-Reply-To: Content-Type: text/plain; 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> ... > } Ah, that's clear now. > > But it doesn't do anything if it's not a call to online a memory block, > so the cached performance data in mempolicy won't change when blocks > are taken offline. > > So the time the scenario you are proposing can arrise is when the device > does not provide performance information (missing CDAT). > > > If a user sets manual mode - they're on the hook to manage everything. > > This is system-wide setting - not a per-task setting. We've yet to see > any strong use-case for individual task weights. If there is a use case > for a task not being subject to system-wide weight changes then it's a > use case for task-local weights. > > ~Gregory Thanks for the explanation. Then except for the nitpicks that I left, I'm fine with this. Thanks, Honggyu