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From: Rik van Riel To: Chris Li , Johannes Weiner Cc: Kairui Song , Nhat Pham , Baoquan He , Shakeel Butt , Kairui Song , Michal Hocko , Roman Gushchin , 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?Q?Baghdasaryan=EF=BF=BC?= , Qi Zheng , Axel Rasmussen , Yuanchu Xie , Wei Xu , Gregory Price , Wenchao Hao , Jonathan Corbet , Hugh Dickins , Baolin Wang , Tejun Heo , Michal =?ISO-8859-1?Q?Koutn=FD?= , 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 Date: Sat, 26 Sep 2026 20:58:44 -0400 In-Reply-To: References: <7ee199ddee81bf8026688def82f78ad9db09be9e.camel@surriel.com> Autocrypt: addr=riel@surriel.com; prefer-encrypt=mutual; keydata=mQENBFIt3aUBCADCK0LicyCYyMa0E1lodCDUBf6G+6C5UXKG1jEYwQu49cc/gUBTTk33A eo2hjn4JinVaPF3zfZprnKMEGGv4dHvEOCPWiNhlz5RtqH3SKJllq2dpeMS9RqbMvDA36rlJIIo47 Z/nl6IA8MDhSqyqdnTY8z7LnQHqq16jAqwo7Ll9qALXz4yG1ZdSCmo80VPetBZZPw7WMjo+1hByv/ lvdFnLfiQ52tayuuC1r9x2qZ/SYWd2M4p/f5CLmvG9UcnkbYFsKWz8bwOBWKg1PQcaYHLx06sHGdY dIDaeVvkIfMFwAprSo5EFU+aes2VB2ZjugOTbkkW2aPSWTRsBhPHhV6dABEBAAG0HlJpayB2YW4gU mllbCA8cmllbEByZWRoYXQuY29tPokBHwQwAQIACQUCW5LcVgIdIAAKCRDOed6ShMTeg05SB/986o gEgdq4byrtaBQKFg5LWfd8e+h+QzLOg/T8mSS3dJzFXe5JBOfvYg7Bj47xXi9I5sM+I9Lu9+1XVb/ r2rGJrU1DwA09TnmyFtK76bgMF0sBEh1ECILYNQTEIemzNFwOWLZZlEhZFRJsZyX+mtEp/WQIygHV WjwuP69VJw+fPQvLOGn4j8W9QXuvhha7u1QJ7mYx4dLGHrZlHdwDsqpvWsW+3rsIqs1BBe5/Itz9o 6y9gLNtQzwmSDioV8KhF85VmYInslhv5tUtMEppfdTLyX4SUKh8ftNIVmH9mXyRCZclSoa6IMd635 Jq1Pj2/Lp64tOzSvN5Y9zaiCc5FucXtB9SaWsgdmFuIFJpZWwgPHJpZWxAc3VycmllbC5jb20+iQE +BBMBAgAoBQJSLd2lAhsjBQkSzAMABgsJCAcDAgYVCAIJCgsEFgIDAQIeAQIXgAAKCRDOed6ShMTe g4PpB/0ZivKYFt0LaB22ssWUrBoeNWCP1NY/lkq2QbPhR3agLB7ZXI97PF2z/5QD9Fuy/FD/jddPx KRTvFCtHcEzTOcFjBmf52uqgt3U40H9GM++0IM0yHusd9EzlaWsbp09vsAV2DwdqS69x9RPbvE/Ne fO5subhocH76okcF/aQiQ+oj2j6LJZGBJBVigOHg+4zyzdDgKM+jp0bvDI51KQ4XfxV593OhvkS3z 3FPx0CE7l62WhWrieHyBblqvkTYgJ6dq4bsYpqxxGJOkQ47WpEUx6onH+rImWmPJbSYGhwBzTo0Mm G1Nb1qGPG+mTrSmJjDRxrwf1zjmYqQreWVSFEt26tBpSaWsgdmFuIFJpZWwgPHJpZWxAZmIuY29tP okBPgQTAQIAKAUCW5LbiAIbIwUJEswDAAYLCQgHAwIGFQgCCQoLBBYCAwECHgECF4AACgkQznneko TE3oOUEQgAsrGxjTC1bGtZyuvyQPcXclap11Ogib6rQywGYu6/Mnkbd6hbyY3wpdyQii/cas2S44N cQj8HkGv91JLVE24/Wt0gITPCH3rLVJJDGQxprHTVDs1t1RAbsbp0XTksZPCNWDGYIBo2aHDwErhI omYQ0Xluo1WBtH/UmHgirHvclsou1Ks9jyTxiPyUKRfae7GNOFiX99+ZlB27P3t8CjtSO831Ij0Ip QrfooZ21YVlUKw0Wy6Ll8EyefyrEYSh8KTm8dQj4O7xxvdg865TLeLpho5PwDRF+/mR3qi8CdGbkE c4pYZQO8UDXUN4S+pe0aTeTqlYw8rRHWF9TnvtpcNzZw== Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.60.2 (3.60.2-1.fc44) MIME-Version: 1.0 X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 8C7768000D X-Stat-Signature: akzc3kn9fumagzaztej3sfe1sqmtpuk1 X-Rspam-User: X-HE-Tag: 1790470822-880713 X-HE-Meta: U2FsdGVkX19e3aBS4wBOHb5XaYhifgGhWGe+nvFuV7ZyZkDv99DGbBHPia3GXCm7EpdBFkm6X0FwuYQw1xUEGv+ElTiyD6oaw85etT0ckqPWYE4uCbUJm7owb1Qj7MNbi0HnquulbSf+riTGLhFTShITXxXdrK7DEAivwSe1ZYO0FSsx/0EF18falfd/ze1Mdzyx3fD+CxLe7EoAuK9jQ/FCQKD0qfxOJN2H5HhrbBVBlPEPAx/FW44XM0ZNHpZLkErjVCh27XTpVNjnPDIQEEO0Rau5QVZvoTouwTJ6/fUJ3QLQsdq8nl9YPQjxqyaQVQ2wqNg9UPcx7xBLPyrR1EHgoUXZOshuJPQO0YbIGQvuAszcyz3Q97lewPahCPkmBPZS5b0fjC7HXNLg5ZwcfQXuz02AZwcWOECTbvWTmr5unFWa3lr7dttY0dk9cIJ5K3Jt0sC/B97GwrtOIm4giFwRT6PWt95xsjwgOnOUhJOnAs9Rg9A+O4Jp0bCAoDtsDBzkrGpHPk3Wo9hD/oPWtLFMCH4Db3yjdLc3Aluz3i6D6BEA9rlMve5f6TN+OF8jdn3Pcd5PprXelxpsmAjsIMvfKXt2MH4dHrDXWMtO3OU4rrhCSW77C2aHlBLNOTQWIZXAD6R7n2y8rHHblq4Lkeyf2pwusAdBYnbURNGOPTtMnNYOSMraQc4eHXOvEk8NZrcPRnLPwqIT0gK+hknvL8YPwueoNqL+EFX1P+Ar9BMtl1QmGCUd4APk9ytGXLBBJEqJGXO5lpn5RchfU3B2Rlqf9TUJgzA1/l4dBuNg4AFzG4pES1x76oRx2L/Ki/lsAZEAUtqdlfIUDCXgaWtc8dtzveAOSVIDBXC79ysYj9eGvbv+dK9B1+fNsBNgCoGbR8EWJTii5aYdOdVW3FNd2hj/F4S2FbOxctodZSz2ig3blTCAFonRumvBAS1f9jZLAhZpc8mWrVzRAYrulpZ ZUHqFexv zfgUXcpHTQHP7+6dsh1ELTiRgch0sAZ+8/xQu1gIxBV5s0n4cwf3ybSoyEFZKf6Xiw2fu6jEbjFMn2yJP7jeiGdLvoiV4SY+EZ2W9EamwckT3IO8pFSNrkSvEAIDoiGvEaPMN1nVDQwsmTJhr1jtWMB7lir/tSedKaw0shJE19Osf2lgrrxGPyk2iBrBWfXlX9YY7E6HWvtcxw+AJEeWORb/y94PMaPpl8jTOeG1jRuYzuM2+4QjSUtl3z5znS710vWoBZHyDdtB8lYlWztoqI4Hpe/rySzMzkQEqVCHTo6LWoZdxQHUnDpMvdtDy9F4Bex9LCqjwhls9OSRS+HC39/uV8ulsA+/MPutwhdeGliydVfP7GQi7ek5Wpx4oK2OsP/bnz8SP7An7SszOZT3bJAhBaLy/DtNOvLmGABv1t28d3PzsA0W009em9iY6yT9WPeU0i7a6JYkmoGY= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sat, 2026-09-26 at 11:27 -1000, Chris Li wrote: > On Fri, Sep 25, 2026 at 5:41=E2=80=AFAM Johannes Weiner > wrote: >=20 > >=20 > > (2) The use case we have. Use memory.swap.max to divide a finite > > space > > in storage. We only have so much space on disk, and we need to > > manage > > fair access. Note that this isn't about speed. We have a mix of > > containers where some use writeback and others do not. The ones who > > write back to the swapfile need to be able to get their fair share > > - > > not more, not less. Including something that doesn't actually > > consume >=20 > Just want to make sure I understand correctly. Do you mean the fair > share of compressed memory used in the zswap case? >=20 Compressed zswap memory is already accounted for under cgroup.memory.max. Compressed zswap memory sits under memory.max together with anonymous, file, and slab cache memory. We do not need or want another limit there,=C2=A0 though I understand other people do. The fair resource use from memory.swap.max is to control how much of the fixed swap file (or swap partition) space each cgroup gets. --=20 All Rights Reversed.