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See http://www.infradead.org/rpr.html X-Stat-Signature: wb5zkm6fc6xf3wc4kzrp69qehsz334zn X-Rspam-User: X-Rspamd-Queue-Id: D0E81402A0 X-Rspamd-Server: rspam02 X-HE-Tag: 1731558938-391174 X-HE-Meta: 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 Ri9MNWO1 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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 Wed, Nov 13, 2024 at 11:07:11PM +0800, Yafang Shao wrote: > + For MADV_HUGEPAGE, the readahead size may exceed this setting > + since its granularity is based on the hugepage size. What does this actually mean? Also this whole read_ahead_kb has been a massive pain, can we maybe take a step back and figure out if we still need it at all, and if yes how we can improve it? In times where we support page cache folio sie up to 1M, having a tiny read ahead window is pretty silly, especially as basically all I/O is done through the "readahead" interface anyway.