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Fri, 30 Oct 2026 03:09:50 -0700 (PDT) Received: from lima-ubuntu.hz.ali.com ([47.246.98.219]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-8a9efe3056dsm555365b3a.43.2026.10.30.03.09.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 30 Oct 2026 03:09:49 -0700 (PDT) From: Qing Wang To: kprateek.nayak@amd.com Cc: bsegall@google.com, davichazbh@gmail.com, dietmar.eggemann@arm.com, juri.lelli@redhat.com, linux-kernel@vger.kernel.org, mgorman@suse.de, mingo@redhat.com, peterz@infradead.org, rostedt@goodmis.org, tim.c.chen@linux.intel.com, vincent.guittot@linaro.org, vschneid@redhat.com, wangqing7171@gmail.com, yu.c.chen@intel.com Subject: Re: [PATCH v4] sched/fair: Replace random newidle_balance with Bresenham accumulator Date: Fri, 30 Oct 2026 18:09:41 +0800 Message-Id: <20261030100941.2500509-1-wangqing7171@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: 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 On Fri, 30 Oct 2026 at 17:46, K Prateek Nayak wrote: > On 10/30/2026 2:49 PM, Qing Wang wrote: > > diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c > > index 919d0fb00bd9..79c477b47510 100644 > > --- a/kernel/sched/topology.c > > +++ b/kernel/sched/topology.c > > @@ -2002,6 +2002,7 @@ sd_init(struct sched_domain_topology_level *tl, > > .newidle_call = 512, > > .newidle_success = 256, > > .newidle_ratio = 512, > > + .newidle_window_pos = 0, > > nit. > > I think this value should start in a way that allows newidle balance to run at > first attempt and then stabilize. Maybe '512; is a good number if not higher? Thanks for the review. The initial value of newidle_window_pos can be any value in [0, 1023]; it only affects when the first balance is allowed, not the spacing of subsequent balances. I'm not sure which value is better here. -- Best regards, Qing