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b=VCYo/kAnidj7WuNhU0XFKQXOcDvDd/yD85UGCv9mwdHK+JS0RAVNF7KU9fdNcSszP q3DhFo9mP3UPpT4llrLK3PAdb015+g1MqHUNYBFjramxw/+NA55SpoMw2afX2FPbqA dPDrYC0TszCnjWWIvp73l9RfsDBQoRQNXw9IyIBwATsuwL5A0YGnxHp3mhXGJxoKb8 njAZvOUs7KjOyK8q9Ej2Ts56p6Z7IYxFXEQhdRxWxhC+cVJOHy+OXR2SI/0ljM79op f59S3iQd7f3v8Vxj3jOhXRLSqucGWsIY3wo0U5HwRNTi9EGGggJzE41xcSGKKM46Rq o3Z/5yWTfsPZA== Date: Thu, 28 May 2026 08:14:23 +0100 From: Lorenzo Stoakes To: wangtao Cc: Pedro Falcato , "catalin.marinas@arm.com" , "will@kernel.org" , "tglx@kernel.org" , "mingo@redhat.com" , "bp@alien8.de" , "dave.hansen@linux.intel.com" , "x86@kernel.org" , "akpm@linux-foundation.org" , "david@kernel.org" , "willy@infradead.org" , "sj@kernel.org" , "kees@kernel.org" , "luizcap@redhat.com" , "zhangjiao2@cmss.chinamobile.com" , "kas@kernel.org" , "hpa@zytor.com" , "liam@infradead.org" , "vbabka@kernel.org" , "rppt@kernel.org" , "surenb@google.com" , "mhocko@suse.com" , "jack@suse.cz" , "riel@surriel.com" , "harry@kernel.org" , "jannh@google.com" , "jgg@ziepe.ca" , "jhubbard@nvidia.com" , "peterx@redhat.com" , "ziy@nvidia.com" , "baolin.wang@linux.alibaba.com" , "npache@redhat.com" , "ryan.roberts@arm.com" , "dev.jain@arm.com" , "baohua@kernel.org" , "lance.yang@linux.dev" , "xu.xin16@zte.com.cn" , "chengming.zhou@linux.dev" , "nao.horiguchi@gmail.com" , "matthew.brost@intel.com" , "joshua.hahnjy@gmail.com" , "rakie.kim@sk.com" , "byungchul@sk.com" , "gourry@gourry.net" , "ying.huang@linux.alibaba.com" , "apopple@nvidia.com" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "linux-mm@kvack.org" , "damon@lists.linux.dev" , "shakeel.butt@linux.dev" , "ryncsn@gmail.com" , "21cnbao@gmail.com" <21cnbao@gmail.com>, "jparsana@google.com" , "dvander@google.com" , zhangji , wangzicheng Subject: Re: [PATCH 0/15] mm: introduce ANON_VMA_LAZY for deferred anon_vma creation Message-ID: References: <20260527110147.17815-1-tao.wangtao@honor.com> <800d894e9a54440fa1d7f7b76e50a45b@honor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <800d894e9a54440fa1d7f7b76e50a45b@honor.com> X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 28520180008 X-Stat-Signature: ibz7ozz5s15mqwatyym9odcrx99me3xh X-HE-Tag: 1779952479-366698 X-HE-Meta: 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 l1WwDHza 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, May 28, 2026 at 06:45:07AM +0000, wangtao wrote: > > > > > > Feedback and suggestions are welcome. > > > > I'm afraid, per previous discussions[1], that no one is really willing to maintain > > extra complexity for the current state of anon rmap and anon vmas. > > Sorry :/ > > > > Also, please don't send series this large without previous discussion and _at > > least_ an RFC tag. > > > > [1] https://lore.kernel.org/all/aec533b2-37a7-4f44-a279- > > c4aa604206ac@lucifer.local/ > > > > -- > > Pedro > > Thank you very much for your reply. > > As I am not very good at english, I haven't participated much in community discussions before and I'm still not very familiar with the usual process. > I realize now that I should probably have started with a discussion thread first, and that this patch series would have been more appropriate with an RFC tag. > I apologize for that. Thanks, appreciate it. It's also for your benefit - regardless of AI usage or not, you've spent time on this needlessly, which a discussion could have avoided. Also as I said, going this way has damaged trust, which also doesn't benefit anybody. mm is a welcoming and open community, the best approach when looking at something like this is to engage with us :) > > I will read the discussion in [1] more carefully. I also noticed the related code here: > https://git.kernel.org/pub/scm/linux/kernel/git/ljs/linux.git/log/?h=project/cow-context > > Many years ago I had already noticed that data structures such as vma, page_table, and anon_vma consume a significant amount of memory. > However, since the mm subsystem is quite complex, I didn't look into it in depth at the time. > Recently, with memory costs increasing, I revisited these structures and analyzed their memory usage again. > Since anon_vma seems to have a relatively smaller impact compared to vma and page tables, I started by exploring possible optimizations for anon_vma first. > > Although anon_vma is relatively simple, there are still quite a few uncertainties. > So I waited until the basic functionality was implemented before sending the patches for discussion. Thanks, I am more than happy to discuss my approach. You can also see slides from my talk on this at LSF/MM at https://ljs.io/talks (Note that the code linked is an incomplete implementation, simply some early code to give a sense of the approach taken!) I would ask, however, in general that you hold off on anything code-wise before I am able to issue my own RFC implementing this approach so we can avoid any overlap/confusion. > > Thanks again for taking the time to reply. > > -- > Tao > Cheers, lorenzo