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charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <0773058df022fa701b78f9a6dfe3c501a1a77351.1705928395.git.baolin.wang@linux.alibaba.com> X-Rspamd-Queue-Id: 491FD4001A X-Rspam-User: X-Stat-Signature: 4c641s6opfx8b1bad7as4gt1sqdnce36 X-Rspamd-Server: rspam03 X-HE-Tag: 1706783413-722608 X-HE-Meta: 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 1BlKp9tC m401KUfwUPVYE+wLf1ycOarm6okJw1W0j3K/Hn3ERfxKduheiMTMJyzZ6OWN/ZsSsxWliCzWB8cxwZvnyE4wnD9uCat+7f3bRizlKzcNWkjkpeVKsyQzqqWlJ25gTNBEBb/6YWv0/9XkzUlkE2G7lp/6ibGT8w01o3sId+6K5Ce0Yx0B1+2cEezEx2bff5IhJzixJKN3Xq/J2DpL3mgyHJUKyATMB2VeJpzWQQqmpa4onQPYTV4+sWnobUcMm1PCDrPsYeYlGQwytcfK1ysCV8SaZE+/EZDJmCeDT23eHnjZDh9A= 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 Mon, Jan 22, 2024 at 09:01:54PM +0800, Baolin Wang wrote: > Currently we will use 'cc->nr_freepages >= cc->nr_migratepages' comparison > to ensure that enough freepages are isolated in isolate_freepages(), however > it just decreases the cc->nr_freepages without updating cc->nr_migratepages > in compaction_alloc(), which will waste more CPU cycles and cause too many > freepages to be isolated. > > So we should also update the cc->nr_migratepages when allocating or freeing > the freepages to avoid isolating excess freepages. And I can see fewer free > pages are scanned and isolated when running thpcompact on my Arm64 server: > k6.7 k6.7_patched > Ops Compaction pages isolated 120692036.00 118160797.00 > Ops Compaction migrate scanned 131210329.00 154093268.00 > Ops Compaction free scanned 1090587971.00 1080632536.00 > Ops Compact scan efficiency 12.03 14.26 > > Moreover, I did not see an obvious latency improvements, this is likely because > isolating freepages is not the bottleneck in the thpcompact test case. > k6.7 k6.7_patched > Amean fault-both-1 1089.76 ( 0.00%) 1080.16 * 0.88%* > Amean fault-both-3 1616.48 ( 0.00%) 1636.65 * -1.25%* > Amean fault-both-5 2266.66 ( 0.00%) 2219.20 * 2.09%* > Amean fault-both-7 2909.84 ( 0.00%) 2801.90 * 3.71%* > Amean fault-both-12 4861.26 ( 0.00%) 4733.25 * 2.63%* > Amean fault-both-18 7351.11 ( 0.00%) 6950.51 * 5.45%* > Amean fault-both-24 9059.30 ( 0.00%) 9159.99 * -1.11%* > Amean fault-both-30 10685.68 ( 0.00%) 11399.02 * -6.68%* > > Signed-off-by: Baolin Wang Acked-by: Mel Gorman -- Mel Gorman SUSE Labs