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See http://www.infradead.org/rpr.html X-Stat-Signature: 5m74d86tp8g5pyq7htngfjrg3fwejqxg X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 2DBF04000C X-Rspam-User: X-HE-Tag: 1684484320-484478 X-HE-Meta: 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 9JbRwZkB SAuq6XZtCu25Bm/byz5e/lrKPbiI8DLxSPx8YwWB0nLKF9qk6JsKqU+fOwfATKjJj8snqGiEYVnxDdyIH485Iw6VUv6A9KMZwhMSSzwipwC6N+qMV+hV4LPIp2nA/NQ/s0W9SKR32JtcZYbJhi612DESL7a74S+Zq/BQhWCf4MyWTOQsvrB2gVso6ReYFvlSR9xUFiBT8RZKdqwxQ7xTDUpJybIfFoYZYk3cRN3RHEUYBN2ik9ir4n+ms+MVwO97GpCVwuY+2oxNil6k9SOjd21bc62GUxPbH6flUllYex6FdG58PsJ8zU6xmZuqpnF4mr6LfkgqzYqcE51vih/hPLh5FvuP5gUSY/l708PwsLANrAC+5OnIQKBSIR2ovxFpjXXPXON6f1kkqqUPUHVxKTOo8k2rmSSfYGw5UDPMO3MvE6606ABpggNym5w== 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: On Fri, May 19, 2023 at 08:49:18AM +0100, David Howells wrote: > direct_splice_read() is then modified to make use of this. This is less > efficient if we know in advance that we want to allocate the full buffer as > we can't so easily use bulk allocation, but it does mean in cases where we > might not want the full buffer (say we hit a hole in DIO), we don't have to > allocate it. Can you eplain the workloads we're trying to optimize for here? To me splice on O_DIRECT is more of a historic accident than an actually good use case..