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Howlett" , Andrew Morton , Chengming Zhou , Johannes Weiner , Jonathan Corbet , Lorenzo Stoakes , Michal Hocko , Mike Rapoport , Nhat Pham , Suren Baghdasaryan , Vlastimil Babka , Yosry Ahmed , kernel-team@meta.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Takero Funaki References: <20250805002954.1496-1-sj@kernel.org> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAmgsLPQFCRvGjuMACgkQTd4Q 9wD/g1o0bxAAqYC7gTyGj5rZwvy1VesF6YoQncH0yI79lvXUYOX+Nngko4v4dTlOQvrd/vhb 02e9FtpA1CxgwdgIPFKIuXvdSyXAp0xXuIuRPQYbgNriQFkaBlHe9mSf8O09J3SCVa/5ezKM OLW/OONSV/Fr2VI1wxAYj3/Rb+U6rpzqIQ3Uh/5Rjmla6pTl7Z9/o1zKlVOX1SxVGSrlXhqt kwdbjdj/csSzoAbUF/duDuhyEl11/xStm/lBMzVuf3ZhV5SSgLAflLBo4l6mR5RolpPv5wad GpYS/hm7HsmEA0PBAPNb5DvZQ7vNaX23FlgylSXyv72UVsObHsu6pT4sfoxvJ5nJxvzGi69U s1uryvlAfS6E+D5ULrV35taTwSpcBAh0/RqRbV0mTc57vvAoXofBDcs3Z30IReFS34QSpjvl Hxbe7itHGuuhEVM1qmq2U72ezOQ7MzADbwCtn+yGeISQqeFn9QMAZVAkXsc9Wp0SW/WQKb76 FkSRalBZcc2vXM0VqhFVzTb6iNqYXqVKyuPKwhBunhTt6XnIfhpRgqveCPNIasSX05VQR6/a OBHZX3seTikp7A1z9iZIsdtJxB88dGkpeMj6qJ5RLzUsPUVPodEcz1B5aTEbYK6428H8MeLq NFPwmknOlDzQNC6RND8Ez7YEhzqvw7263MojcmmPcLelYbfOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCaCwtJQUJG8aPFAAKCRBN3hD3AP+DWlDnD/4k2TW+HyOOOePVm23F5HOhNNd7nNv3 Vq2cLcW1DteHUdxMO0X+zqrKDHI5hgnE/E2QH9jyV8mB8l/ndElobciaJcbl1cM43vVzPIWn 01vW62oxUNtEvzLLxGLPTrnMxWdZgxr7ACCWKUnMGE2E8eca0cT2pnIJoQRz242xqe/nYxBB /BAK+dsxHIfcQzl88G83oaO7vb7s/cWMYRKOg+WIgp0MJ8DO2IU5JmUtyJB+V3YzzM4cMic3 bNn8nHjTWw/9+QQ5vg3TXHZ5XMu9mtfw2La3bHJ6AybL0DvEkdGxk6YHqJVEukciLMWDWqQQ RtbBhqcprgUxipNvdn9KwNpGciM+hNtM9kf9gt0fjv79l/FiSw6KbCPX9b636GzgNy0Ev2UV m00EtcpRXXMlEpbP4V947ufWVK2Mz7RFUfU4+ETDd1scMQDHzrXItryHLZWhopPI4Z+ps0rB CQHfSpl+wG4XbJJu1D8/Ww3FsO42TMFrNr2/cmqwuUZ0a0uxrpkNYrsGjkEu7a+9MheyTzcm vyU2knz5/stkTN2LKz5REqOe24oRnypjpAfaoxRYXs+F8wml519InWlwCra49IUSxD1hXPxO WBe5lqcozu9LpNDH/brVSzHCSb7vjNGvvSVESDuoiHK8gNlf0v+epy5WYd7CGAgODPvDShGN g3eXuA== Organization: Red Hat In-Reply-To: <20250805002954.1496-1-sj@kernel.org> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: MPI5H5roHzzKF1Sq7vn5Uf4I3ozao-vWDnX-jkWPbIk_1754390859 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: B1DF0180003 X-Stat-Signature: r1p7fsauy1wfr9h7guoaq7b46qf3dcfi X-HE-Tag: 1754390863-717918 X-HE-Meta: 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 pDo1kFw2 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 05.08.25 02:29, SeongJae Park wrote: > When zswap writeback is enabled and it fails compressing a given page, > the page is swapped out to the backing swap device. This behavior > breaks the zswap's writeback LRU order, and hence users can experience > unexpected latency spikes. If the page is compressed without failure, > but results in a size of PAGE_SIZE, the LRU order is kept, but the > decompression overhead for loading the page back on the later access is > unnecessary. > > Keep the LRU order and optimize unnecessary decompression overheads in > the cases, by storing the original content in zpool as-is. Does this have any effect on the movability of the given page? IOW, does page migration etc. still work when we store an ordinary page of an shmem/anon folio here? -- Cheers, David / dhildenb