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s=arc-20220608; t=1740460013; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=pr8eMhZQSHFZY6jxHpAIsHORIN1p2RTiGf5A6SYPFZg=; b=pNd+9bnitugsg4sV8pTXN8GSQU62vKUJIgg3KtNbofa78tS0E6O29OZIn0MIYE3BUkH4p2 YIdsLIwunNkUPb7waFj9sXGFYCngYWyvP1N2ZrLDLmMyt6ctjkkkZpdrELMaiswFnidQnT NUlcSnipq2usqu5UtCptyr+QTHhwz5Q= X-AuditID: a67dfc5b-3c9ff7000001d7ae-fd-67bd4fe9fbfd Date: Tue, 25 Feb 2025 14:06:43 +0900 From: Byungchul Park To: Gregory Price Cc: "Harry (Hyeonggon) Yoo" <42.hyeyoo@gmail.com>, Honggyu Kim , kernel_team@skhynix.com, Matthew Wilcox , lsf-pc@lists.linux-foundation.org, linux-mm@kvack.org, linux-cxl@vger.kernel.org Subject: Re: [LSF/MM/BPF TOPIC] Restricting or migrating unmovable kernel allocations from slow tier Message-ID: <20250225050643.GB38036@system.software.com> References: <20250207072024.GA48419@system.software.com> <20250210071741.GB39454@system.software.com> MIME-Version: 1.0 Content-Type: text/plain; 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You seem to mean those works should be serialized. Right? If it > > should be for some reason, then it could be sensible. > > > > I'm suggesting that there isn't a strong reason (yet) to consider such a > complicated change. As Willy has said, it's a fairly fundamental change > for a single-reason (CXL), which does not bode well for its acceptance. > > Honestly trying to save you some frustration. It would behoove you to > find stronger reasons (w/ data) or consider different solutions. Right > now there are stronger, simplers solutions to the ZONE_NORMAL capacity > issue (struct page resize, huge pages) for possible capacities. > > I also think someone should actively ask whether `struct page` can be > hosted on remote memory without performance loss. I may look into this. Could you share the plan or what you have been thinking about it? We'd be happy to discuss this topic together, and furthermore, it'd be even better to work on it together. Byungchul > ~Gregory