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[173.79.60.52]) by smtp.gmail.com with ESMTPSA id af79cd13be357-93c1cf0dcd9sm181244085a.4.2026.09.22.08.20.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 22 Sep 2026 08:20:49 -0700 (PDT) Date: Tue, 22 Sep 2026 11:20:47 -0400 From: Gregory Price To: Chris Li Cc: Rik van Riel , Johannes Weiner , Baoquan He , Nhat Pham , Kairui Song , Michal Hocko , Roman Gushchin , Shakeel Butt , Yosry Ahmed , David Hildenbrand , Muchun Song , Kemeng Shi , Barry Song , YoungJun Park , Chengming Zhou , "Lorenzo Stoakes (Oracle)" , "Liam R. Howlett" , "Vlastimil Babka (SUSE)" , Mike Rapoport , Suren =?utf-8?B?QmFnaGRhc2FyeWFu77+8?= , Qi Zheng , Axel Rasmussen , Yuanchu Xie , Wei Xu , 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 , Kairui Song , Joshua Hahn Subject: Re: Path forward for Virtualized Swap? Message-ID: References: <785353ef79844e81a8cd97e87b00ef1f785b15e5.camel@surriel.com> <83539be885f15bb567b30264f5f62e718f4a9fd0.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 Tue, Sep 22, 2026 at 03:32:44AM -1000, Chris Li wrote: > > Right now it has 64GB of memory. > > That is exactly my point. You are running 1/8 = 12.5% system ram. > Chris you are missing the point Zswap: 8812236 kB Zswapped: 24927876 kB To support this, you'd need to know you were going to get a 3:1 compression ratio and allocate 24GB of storage (24GB of swap slots). An hour from now he might run a workload that's 4:1 compressible and there would be 32GB zswapped - but if he'd only allocated 24GB of swap he'd be limited to 24GB arbitrarily. On a 1.5 TB server, that number is oppressive. It's 192GB of potentially dead storage space. At 1 million servers that up to 183 Petabytes of pointless provisioned flash if you know that most of the memory is zswappable. You're focused on the wrong problem. ~Gregory