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Rao's message of "Fri, 20 Jun 2025 14:28:33 +0530") References: <20250616133931.206626-1-bharata@amd.com> <87bjqi3ohx.fsf@DESKTOP-5N7EMDA> Date: Fri, 20 Jun 2025 17:59:52 +0800 Message-ID: <87zfe220o7.fsf@DESKTOP-5N7EMDA> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain; charset=ascii X-Rspamd-Server: rspam11 X-Rspam-User: X-Rspamd-Queue-Id: 8913B1C0006 X-Stat-Signature: 9c4drdrxbknqka8j7s5s64nnnaia34bf X-HE-Tag: 1750413602-962025 X-HE-Meta: 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 +ef+xBDC EvSKfdmgFP/URPKpGYP99Tm7CiwLfUAtj65xOhv/1xsoWDfyrynE9bw/tg4m/HWSDxJgDgCm/x9OS4pI8TR/Durydp15BRt9zAVDDOoXbAP6GrD21hNMD92y/c1K15HiDz0lXLazAB5IaUijBAs06AVqiJu7Cn70XUN+XyoztcLN6ZRZDR+HFB/WQav0SLsgGaD/aKsuFBtURNeE8LhRmvi4p5eJ+R9Plx9PPCLevyphcoCBHJOtOKF7o539vXObQFjpodtc7d4YFz9WSSvevRkU23fAYgOEiTP69/uT+ModUeapsOUUoDUFENMh50MU3AcbGasEoeRjd58QUK9vak86VUyP6Km3IdkLZu5+hOeFAoZty3jQaMX610g== 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: Bharata B Rao writes: > On 20-Jun-25 12:09 PM, Huang, Ying wrote: >> Bharata B Rao writes: >> >> >> I don't think page flag + scanning is a good idea.If the > > If extended page flags is not the ideal location (I chose it in this > version only to get something going quickly), we can look at maintaining > per-pfn allocation for the required hot page metadata separately. > > Or is your concern specifically with scanning? What problems do you > see? > > It is the cost or the possibility of not identifying the migrate-ready > pages in time? Or something else?? We may need to scan a large number of pages to identify a page to promote. This will waste CPU cycles and pollute cache. --- Best Regards, Huang, Ying