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[66.183.142.209]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-8249e80c0a7sm3743153b3a.45.2026.02.11.15.25.04 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 11 Feb 2026 15:25:04 -0800 (PST) From: "Doug Smythies" To: "'Peter Zijlstra'" , "'Vincent Guittot'" Cc: "'K Prateek Nayak'" , , , , , , , , , , , "Doug Smythies" References: <20260130093439.803225718@infradead.org> <4c48fe59-8ff3-41fb-83cb-869409f6fbc6@amd.com> <20260203111134.GL1282955@noisy.programming.kicks-ass.net> <38ef3462-4c4e-4f40-8d63-84dd71cbd043@amd.com> <20260209154718.GW1282955@noisy.programming.kicks-ass.net> <002501dc9b16$442a7050$cc7f50f0$@telus.net> <20260211090144.GY1282955@noisy.programming.kicks-ass.net> <20260211104833.GH1395416@noisy.programming.kicks-ass.net> In-Reply-To: <20260211104833.GH1395416@noisy.programming.kicks-ass.net> Subject: RE: [PATCH 0/4] sched: Various reweight_entity() fixes Date: Wed, 11 Feb 2026 15:25:06 -0800 Message-ID: <004001dc9bad$a86d5fe0$f9481fa0$@telus.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 16.0 Content-Language: en-ca Thread-Index: AQK5IwR5loYZhW90rhLC3Nnzvp6wgAGWA92PAlBHLF4B5k73QgEcsVRAAlcnOhYDFmLm8wGuW2zjAlK+Dh4A5A0FgwJtnXszsyfEkVA= On 2026.02.11 02:49 Peter Zijlstra wrote: > On Wed, Feb 11, 2026 at 10:01:44AM +0100, Peter Zijlstra wrote: > >>> There 2 issues with patch 3 >>> >>> *one scale_load_down remains in avg_vruntime >>> >>> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c >>> index 25c398ff0d59..3143ae7f07b0 100644 >>> --- a/kernel/sched/fair.c >>> +++ b/kernel/sched/fair.c >>> @@ -778,7 +778,7 @@ u64 avg_vruntime(struct cfs_rq *cfs_rq) >>> >>> if (weight) { >>> if (curr) { >>> - unsigned long w = scale_load_down(curr->load.weight); >>> + unsigned long w = >>> avg_vruntime_weight(curr->load.weight); >>> >>> runtime += entity_key(cfs_rq, curr) * w; >>> weight += w; >> >> AAARGHHH!! Sorry about that, clearly I've not been careful with >> reshuffling patches :-( > > So with that one fixed; I get (as queue/sched/core of just now): > ... snip... For the Phoronix version of hackbench I now get (I call this "V3"): Run 1 of 2, 10 tests per run: 22.875 seconds average, Deviation 0.25% Run 2 of 2, 10 tests per run: 22.979 seconds average, Deviation 0.16% Test conditions same as yesterday for "V2" (was 85.755 seconds average, deviation 3.33%) Processor Test Configuration 8 and "Process". Conclusion: great. > Now let me go check on that latency thing from Doug (although hopefully > that was the same boo-boo). I am starting that test now. ... Doug