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Tue, 27 Oct 2026 02:31:52 -0700 (PDT) Received: from lima-ubuntu.hz.ali.com ([47.246.98.219]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-3ae406153fesm3000707a91.5.2026.10.27.02.31.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Oct 2026 02:31:52 -0700 (PDT) From: Qing Wang To: wangqing7171@gmail.com, peterz@infradead.org Cc: bsegall@google.com, chenl311@chinatelecom.cn, dietmar.eggemann@arm.com, juri.lelli@redhat.com, kprateek.nayak@amd.com, linux-kernel@vger.kernel.org, mgorman@suse.de, mingo@redhat.com, rostedt@goodmis.org, vincent.guittot@linaro.org, vschneid@redhat.com Subject: Re: [PATCH v2] sched/fair: Replace random newidle_balance with Bresenham accumulator Date: Tue, 27 Oct 2026 17:31:42 +0800 Message-Id: <20261027093142.2337191-1-wangqing7171@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260602054619.637201-1-wangqing7171@gmail.com> References: <20260602054619.637201-1-wangqing7171@gmail.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Peter, Gentle ping on this. I know you're busy, but I'd really appreciate your thoughts. > I took the most sensitive workload I have for newidle balance (tbench) > and took it for a spin with these changes. Following are the results: > > Clients: tip bresenham_accm > 1 321.65 (0.00 pct) 313.97 (-2.38 pct) > 2 641.92 (0.00 pct) 638.74 (-0.49 pct) > 4 1245.65 (0.00 pct) 1237.26 (-0.67 pct) > 8 2435.80 (0.00 pct) 2442.23 ( 0.26 pct) > 16 4717.66 (0.00 pct) 4688.19 (-0.62 pct) > 32 9303.53 (0.00 pct) 9390.71 ( 0.93 pct) > 64 18002.57 (0.00 pct) 17911.56 (-0.50 pct) > 128 27729.26 (0.00 pct) 27621.95 (-0.38 pct) > 256 47134.77 (0.00 pct) 46137.36 (-2.11 pct) > 512 43179.41 (0.00 pct) 43277.53 ( 0.22 pct) > 1024 40339.30 (0.00 pct) 40176.49 (-0.40 pct) > > The %diff is in noise range which is a good indication that there > shouldn't be any surprises. I'll queue a run overnight to see if > there are other benchmarks that like / dislike these changes. This benchmarks looks good from Prateek. Link: https://lore.kernel.org/all/da1896b3-6bec-4b56-bf6d-9ce775b00b8d@amd.com/ Cc: K Prateek Nayak -- Best regards, Qing