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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: A073C20015 X-Stat-Signature: ddhknsig4xr9c9hmh5mc9iwx17fdr38g X-Rspam-User: X-HE-Tag: 1733992171-692657 X-HE-Meta: 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 Al0HSwvr 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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 Thu, Dec 12, 2024 at 08:37:11PM +1300, Barry Song wrote: > From: Barry Song > > While developing the zeromap series, Usama observed that certain > workloads may contain over 10% zero-filled pages. This may present > an opportunity to save memory by mapping zero-filled pages to zero_pfn > in do_swap_page(). If a write occurs later, do_wp_page() can > allocate a new page using the Copy-on-Write mechanism. Shouldn't this be done during, or rather instead of swap out instead? Swapping all zero pages out just to optimize the in-memory representation on seems rather backwards.