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Howlett" , "Vlastimil Babka (SUSE)" , Mike Rapoport , Suren =?utf-8?B?QmFnaGRhc2FyeWFu77+8?= , Qi Zheng , Axel Rasmussen , Yuanchu Xie , Wei Xu , Gregory Price , Wenchao Hao , Jonathan Corbet , Hugh Dickins , Baolin Wang , Tejun Heo , Michal =?utf-8?Q?Koutn=C3=BD?= , Shuah Khan , Kunwu Chan , Meta kernel team , Linux Memory Management List , Linux Kernel Mailing List , linux-doc@vger.kernel.org, "open list:CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG)" , Andrew Morton , Joshua Hahn Subject: Re: Path forward for Virtualized Swap? Message-ID: References: <7ee199ddee81bf8026688def82f78ad9db09be9e.camel@surriel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Sep 25, 2026 at 12:36:46PM +0800, Shakeel Butt wrote: > On Fri, Sep 25, 2026 at 09:15:17PM +0800, Kairui Song wrote: > [...] > > Thanks Kairui for very clear description of what you want and looking for. > After reading your email, I think you want memsw support in v2. Currently you > somehow are implementing memsw using memory.current and memory.swap.current. > (I am assuming you need to subtract swapcache to avoid double counting.) > To conclude, you want to use vswap (the aim is it to default) but you still want > your way to implementing memsw keep working. > > Please correct me if I missed something. > > I am wondering if you really want memsw, why not propose memsw. Someone from > tencent proposed memsw [1] previously, so why not continue that effort? I am > pretty sure folks from Google (people who actually work on prodkernel there) > will be happy to collaborate with you on that. Hi Shakeel, Right, I believe it is still being proposes as you can see there are some previous progress, year that work need updated, let me try to do something about it. > > [1] https://lore.kernel.org/20250319064148.774406-1-jingxiangzeng.cas@gmail.com/ > > Setting aside the memsw conversation, I think we should go back to the actual > vswap conversation and list down what we agree on and where we still need > discussion and decision. (I will take a stab at it and start a separate thread > but still on this email and will use AI for the summary.) Right, the things here is that I think it's not hard to see that memory.current / memory.swap and memsw (if in V2) is tangled with each other so I'm hope we won't create blocker for the future.