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Howlett" , Juan Yescas , android-mm , Vlastimil Babka , Michal Hocko , Johannes Weiner , Nhat Pham Subject: Re: [LSF/MM/BPF TOPIC] Optimizing Page Cache Readahead Behavior Message-ID: References: <31e946de-b8d5-4681-b2ac-006360895a87@lucifer.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <31e946de-b8d5-4681-b2ac-006360895a87@lucifer.local> X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: B70D7C0006 X-Stat-Signature: g98bimfg8jn8g5czbc7o5cit73ijzwkz X-HE-Tag: 1740313498-279229 X-HE-Meta: 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 tgtoKjSp faXI3m0PM+9LiEKXoxVb21mtZUKkD5BvLGu4owJz1eBFqUdj1J8Z5JAX2C9VZ4p0mp4ZXmaknej0nQS4JnMQoz/2kg0sDuNxUEePwmPuoikPObb647R8z5Tw4GJA8oyAqKSYrhKR0q6163zl1d36WbCofmbdhdz+GGykubOVGWk1hLYNS0PowBdofy+k7KaNwUhvONNjVQ6xK2SNIXfxAGvqxsyiGMOSiBl7dWXSOMfYNkwX88LXMNC1XgOAXivR2ksaSjtT1isIPdHHWhcHpCu12UtS8o/q3EHpvyeuNkgsiV42mp88tu8q7d7Ka9ojzAQT8 X-Bogosity: Ham, tests=bogofilter, spamicity=0.008913, 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 Sun, Feb 23, 2025 at 09:30:57AM +0000, Lorenzo Stoakes wrote: > It seems strange to me sparse regions would place duplicate zeroed pages in > the page cache... https://lore.kernel.org/linux-mm/Z7p-SLdiyQCknetc@casper.infradead.org/