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To: Chris Li Cc: Rik van Riel , Baoquan He , Shakeel Butt , Kairui Song , Johannes Weiner , 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 , =?UTF-8?Q?Suren_Baghdasaryan=EF=BF=BC?= , Qi Zheng , Axel Rasmussen , Yuanchu Xie , Wei Xu , Gregory Price , Wenchao Hao , Jonathan Corbet , Hugh Dickins , Baolin Wang , Tejun Heo , =?UTF-8?Q?Michal_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 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Sun, Sep 20, 2026 at 5:13=E2=80=AFPM Chris Li wrote: > > That is not what I have in mind. The example I have in mind is that > zswap is charged to swap counters. Changing that behavior will break > our current deployment and that of many other. Kairui give some > example as well. That behavior should not change. We already have a knob to select vswap. Users can turn it off initially, and/or update their software to handle the transition based on this knob. Otherwise, you'd never be able to introduce any behavior into the kernel. Hugetlb accounting/charging is a new behavior, and there were softwares written before that assumed hugetlb usage is not charged. If it's not a good argument to block the implementation of hugetlb accounting then, it's not a good argument now.