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From: Rik van Riel To: Chris Li Cc: Johannes Weiner , 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: Sun, 27 Sep 2026 08:29:21 -0400 In-Reply-To: References: <7ee199ddee81bf8026688def82f78ad9db09be9e.camel@surriel.com> <9499bc084e30df4d10bc069ed26d576e4dd3de80.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-Stat-Signature: ceauxq1fkmer3tb8b6xa8thhmtbitede X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: B4C9F1C000B X-HE-Tag: 1790512238-870070 X-HE-Meta: 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 qBnGIYrd 5iRZ86/NeHzWyIQE2p88BAmGXOOYBal7fYGFizFDjxgeo4Ij9kZ1OSryZ/DX02sCoNN284NgfSvemRxU54WnFmLG2kEwewIW2N13dOD0R5icBcL+lQ1Ij/bMSRJvyoC1iK5O5oOAUTFNg/zqLvN27OUheyHKxAfqnhaGs9Chfv8jNh4xX8/E6jfrJLUz1glGmCPnoqS4lmo3sRBimFwOipaxRHhrnps5c34W6LnhTBr6fWF1XdBqs50ivUDu2fD+wPg2tHsJvd5lOlwcl7AN+wFjzS3uWvkNZMmw//F+aoTsJGLZZdIjVILkf2qxRZoBw+9Bt0zujKzhSvHRXG2FWaqc+jrsgWHPJ3Kea9vAbULaWVZoL//eB91gbCloe0AI4Sgx8wSrKpAYmH0JjafAEbMs6pRbG+6rTIppoSwtrZ26Jwjchn6jjSsnIbbvk0Q5Gw7/ER23FkynzgYI= 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 20:23 -1000, Chris Li wrote: > On Sat, Sep 26, 2026 at 2:59=E2=80=AFPM Rik van Riel > wrote: >=20 >=20 > > 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 > That is the part I am not sure I understand correctly. Fair in what > sense? Using the swap file proportional to the memory limit of the > cgroup? Do you have an example of perfectly fair swap file usage for > a > cgroup with an 8G memory limit versus one with a 1G limit? >=20 > Sorry I am a bit slow grasping what exactly the fair behavior is. Say we have a 64GB swap file, and several cgroups on the system, applications A & B, and system.slice. We might give system.slice a 10GB memory.swap.max,=C2=A0 and each application a 25GB memory.swap.max. This way a memory leak in application B does not result in application A being unable to run. The thing that leaks (if anything) ends up=C2=A0 getting killed, not the innocent bystander.=20 --=20 All Rights Reversed.